Natural Stone Institute Announces 2020 Stone Industry Education Series


Oberlin, OH, January 14, 2020—The Natural Stone Institute and Stone World magazine are pleased to announce the schedule for the 2020 Stone Industry Education Series. Stone Summits will be held in nine cities across the United States.

The nine Stone Summits scheduled for 2020 will cover topics relevant to stone fabricators, including maximizing shop efficiency and profits, using metrics to measure success, understanding OSHA safety regulations, and creating a plan for finding and retaining top talent. 2020 Stone Summits will be facilitated by a team of experienced industry leaders including GK Naquin, Duane Naquin, Tony Malisani, and Eric Tryon.

2020 Stone Industry Education Series:

February 27

Arkansas Stone Summit: 12 Business Axioms

Pacific Shore Stones

Mabelvale, AR

March 12

California Stone Summit: Stone Shop Management

MSI

Orange, CA

April 2

Colorado Stone Summit: Know Your Business

Arizona Tile

Denver, CO

May 7

Massachusetts Stone Summit: Key Pulse Points for Building a Successful Stone Fabrication Business

Daltile

Westwood, MA

June 4

New Mexico Stone Summit: Key Pulse Points for Building a Successful Stone Fabrication Business

Arizona Tile

Albuquerque, NM

July 16

Oregon Stone Summit: Stone Shop Management

MSI

Tualatin, OR

September 17

Illinois Stone Summit: Know Your Business

Universal Granite & Marble

Chicago, IL

October 8

Alabama Stone Summit: Stone Shop Management

Triton Stone Group

Birmingham, AL

November 5

Texas Stone Summit: 12 Business Axioms

MSI

Austin, TX

To learn more about each event, visit www.stoneindustryeducation.com

Tile and bath safety

With all the beautiful tile available today, it is sometimes difficult to make the perfect choice. However, when considering your selection of a floor tile in a stall shower, many decisions need to be made to ensure a safe environment.

Many times, the tile selection process for a shower floor is focused on the aesthetics of the installation being a beautiful blend of products that will further enhance the overall project. But the primary goal here is to obtain tile that will yield a safe surface on which to stand while using the shower. 

The TCNA Handbook does offer some helpful information that can guide the selection of the appropriate floor tile. Under the header, “Coefficient of Friction and the DCOF AcuTest®”, it states the following: The DCOF (Dynamic Coefficient of Friction) measures the dynamic friction, which is the frictional resistance one pushes against when already in motion. Under this test, a slip occurs when pushing off with more force than the surface can resist. Tile which is tested to this protocol yields a minimum wet DCOF AcuTest value of 0.42 for ceramic tiles for level interior spaces expected to be walked upon when wet. 

A clean crisp look featuring a single slope shower floor leading to a linear drain along the base of the shower seat. Image courtesy of Daltile.

While this test does not identically mimic the process of standing in the shower (not walking) and is not level due to the slope to the drain, it does provide some guidance as to which tile may function better in wet conditions.

The Handbook further makes this statement: “According to the standard, tiles with a wet DCOF AcuTest value of less than 0.42 are only suitable for floor areas that will be kept dry. Polished tiles generally fall into this category.” Caution should be exercised when considering high-fashion polished tiles that are pleasing to the eye, but offer little resistance to slipping, especially when combined with soap, shampoo, and water. 

For years the popular and functional selection of shower floor tiles resided with a 1” x 1” or
2” x 2” mosaic tile as shown in the attached photo. This small facial surface area tile provides a significant number of grout joints that can aid in providing a surface that offers good traction. 

However, today’s consumers are demanding the use of larger tiles that offer a sleek look that slope to a linear drain located either in the center of the floor or at the intersection of the wall. These large-format tiles look great on the shower floor and offer a look not available in the past. Imagine combining a realistic woodgrain plank floor with a gorgeous marble wall that both offer the benefits of a porcelain tile.  

After the tile has been selected and properly installed, the appropriate maintenance regimen must be instituted. Normally, a pH-neutral cleaner will work well for routine cleaning. However, if a residue of soap scum, body oil, shampoo, and/or cream rinse accumulate on the floor surface, the use of a high-alkaline cleaner may be needed remove the build-up. As always, carefully follow the directions on the container to ensure thorough cleaning and a trouble-free tile installation that will stand the test of time.

Installing tile when a pattern is involved

Michael Moreno noted, “The tile itself isn’t a handmade tile, but they are somewhat irregular on all six sides and the installation did have its difficulties because of this. Experience is key in these situations.”

Installing ceramic tile can be challenging enough in itself, but when the job calls for a tile pattern, life for contractors and installers can get more difficult than usual. There are several different obstacles in play when it comes to putting down a tile pattern, and it’s part of the job for the contractor to recognize, assess and overcome each as they present themselves.

According to Michael Moreno, Owner, Artisan Tile, Lompoc, Calif., tile patterns, generally, aren’t difficult. “The problems I have run into are when the pattern is on an irregular or handmade tile,” he said. “Patterned handmade tile can and does cause problems when taking a change of plane. The pattern and the tile often want to do two separate things. 

“Change of plane with a handmade tile is already problematic in matching joints,” he explained, “especially on a diagonal. Add a pattern onto the tile and it can be a tug of war between matching the joints and pattern. It becomes a game of averaging between the two.”

The J&R Tile team precut, dry-laid, and asked for approval prior to installation. The octagons in this project were five different pieces.

As Erin Albrecht, principal/executive vice present, J&R Tile, San Antonio,Texas, noted, two different thicknesses are always a challenge, and scribing and inlay work with porcelain can be difficult when not using the right tooling and blade setup. “A ‘random’ (not to scale, artistic freedom of installer) is always a little nerve racking when a designer wants something to be an organic outline or interpretation of a drawing.

“That freedom of the installation team can make us nervous at times,” she explained, “versus a formal drawing, because of the design intent’s risk of being lost in interpretation and an owner/client being disappointed by the outcome.”

Martin Brookes, founder/owner, Heritage Marble & Tile, Mill Valley, Calif., believes partnering with material manufacturers and asking for job-specific installation materials reduces the risk of failure, while presenting the scope of work to the client gains their trust in his company’s ability to perform the task. 

“Everything is dry-laid, and issues are discussed ahead of time so the expectation can be achieved,” Brookes explained. “Careful reading of all tile and setting material literature is done prior to starting the job. We have an understanding of how critical the layout can be. Even with a perfect installation, if this is overlooked, the install can fall short of expectations.”

According to Sal DiBlasi, the secret to installing patterned tile is all about planning and communication with the owner to explain what the plan is, what is possible and what is unfeasible.

Sal DiBlasi, owner, Elite Tile Co., Medford, Mass., believes the difficulty inherent with pattern tile jobs depends on the type and size of the tile, and the pattern being installed. “If it is a larger tile with a complicated repeating pattern involving several sizes of tile, just keeping the pattern correct can be a challenge,” DiBlasi said. 

Like Brookes, he believes layout is “another headache. You need to be sure to get decent size cuts,” he explained. “This can be time consuming and has to be correct, since once you start installing tile, it cannot be changed. I’ve found that using the smallest tile as a unit to figure out the layout will generally make it easier. The layout becomes much harder when you must consider kitchen cabinets, an island, and if the floor branches out into other areas.”

Another challenge, said DiBlasi, is size, which apparently really does matter. For smaller, or mosaic tiles, he noted, you want to avoid having tiny cuts at thresholds at the tub or where they’ll be visible. “If you can’t avoid them, lay out the floor so all the ‘bad’ cuts will be in inconspicuous areas or where they’ll be covered,” DiBlasi said. 

If the area is symmetrical, he explained, “then balance is another important consideration. “You don’t want the area to look lopsided or uneven. Grout is another concern: Do you want the pattern to be the dominant visual effect, or do you want it to be subdued? A contrasting grout will make the pattern stand out, while a grout that blends will pull the color and texture of the tile to the eye.”

How should contractors overcome tile pattern problems? According to Moreno, it’s all about doing it. “Understanding what you are looking at and what you need to do to fix it comes with experience.”

DiBlasi concurs, and said, in addition to planning and communication, having 35 years in the business means he can draw on the experience of past projects to help figure out what to do next. “This isn’t to say new challenges don’t arise, but having that many years as an installer really helps.”

Martin Brookes noted, when it comes to working with pattern tile, his firm makes sure the installers never feel pressured into installing tile until the layout is approved. “Earlier in the year we did a mosaic wall. We knew it would be challenging, and the contractor was nervous, given he had a previous experience with the same tile that failed. He had many questions, which we answered with confidence. The artist, Johanna Poethig, was heavily involved in the layout. Her vision came to fruition and the rendition almost mirror imaged the finished project. This collaboration and patience really paid off and everyone was happy with the end results.”

Is installing tile over sheet vinyl goods still a “questionable substrate”?

QUESTION

Can you please tell me where to locate in the 2019 TCNA Handbook information to determine if installing tile over sheet vinyl goods is still a “questionable substrate”? I do not see any ANSI specs that reference installing tile over glue-down sheet vinyl as an option. Is there a spec for this?

ANSWERS

There is not an ANSI specification or a TCNA Handbook method or detail for installing tile over sheet vinyl goods. The NTCA Reference Manual lists sheet vinyl as a questionable substrate. 

However, many manufacturers produce mortars that may be used to install tile over sheet vinyl provided it is fully adhered (not simply edge glued) and non-cushioned. Should you choose to do this, it is critical to follow the mortar manufacturer’s instructions.

It is vital that that you use an appropriate cleaner to remove all wax and surface contaminants from the vinyl. I recommend you do not sand or abrade the surface of the vinyl as some products may contain asbestos. 

– Mark Heinlein, NTCA Training Director


The list of questionable substrates is found in the 2019-2020 NTCA Reference Manual on page 31. They are not listed in the TCNA Handbook. There is, however, a method for renovations in the Handbook on page 288, Method TR711. It states “Ideally, existing finishes should be completely removed so the tile work can be placed on the substructure. This isn’t always practical, and as previously stated, some mortar manufacturers will warranty installations over vinyl flooring, provided they meet certain criteria.” TR711 goes on to give general guidelines for renovations. 

– Rodd Roderick, NTCA Technical Trainer

Synergy amongst the trades: How teamwork makes the dream work

Fast-track construction projects often can be ultra-fast paced and hectic. They require industry professionals across several different trades to blend together for a common goal – getting the project done correctly and on time for the client. 

How well – or not well – trade professionals synergize can directly affect the outcome of most any project. In many instances, the vision of cohesiveness and synchronicity among these different units becomes just that: a vision never to be realized; a goal that never reaches fruition, much to the chagrin of architects and designers.

In what ways can trade professionals come together to make sure the job gets done right, to have “the big picture” be realized to the satisfaction of all? According to Karl Parker, owner/president, All American Design & Construction, Albuquerque, N.M., an eagerness to learn is just as critical as the need to work together in order for professionals and projects to realize their true potential.

In New Mexico, Parker noted, there is a different feel and respect for when work among varying trades overlap. “Big steps have been taken with plumbers and inspectors working with tile installers on complex shower installations. Everyone is eager to learn about these products and excited about the overall outcome of install performance.”

As Lee Callewaert, owner, Dragonfly Tile & Stone Works, Grafton, Wis., espoused, nothing is more critical to multiple trades working together successfully than the relationships built while on the job. “We’re fortunate to work in a specific market that brings some of the best trades together,” he said. “We’ve had the opportunity to work with some of the same people on multiple projects. 

According to Jane Callewaert, this is an example of the kind of enhancements her husband, Lee, is able to add to projects because he works so closely with the other trades. “In this case, the cabinet maker was able to adjust his drawer fronts in advance so Lee could add custom marble insets.”

“When the relationships are built on mutual respect and the various trades are working together for the same goal (making the end result the very best it can be for the client),” Callewaert added, “all the trades involved develop a positive reputation in the market. 

“We have general contractors, architects, homeowners, etc., who hire us and some of the same other trades for all their projects because they know that this group of professionals will make their job so much easier,” Callewaert added. “We will rarely come to them with an issue as we work together and solve the problems ourselves.”

Parker agreed, and noted a specific instance in which an opportunity to join a trade association brought professionals together in the same room for a common cause. “One aspect I can speak about from the trade gap is, being invited to join the International Association of Plumbing and Mechanical Officials (IAPMO). The depth of this association runs from code (UPC) to reviewing our own products for listing and acceptance for sales.

“From my very first meeting, it was all about open arms and further invitations to run CEU programs for the union and plumbing officials,” Parker explained. “It seems as though the big gap in trade is with officials and actual plumbers.”

Callewaert echoed Parker’s sentiment, saying that when the trades work together, you are better able to achieve a positive outcome for the customer, which is the ultimate goal. “When working together as a team, everyone has that same goal in mind,” Callewaert said. “The projects that involve multiple trades with mutual respect are consistently of higher quality and result in much happier clients.”

Reiterating the relationship theme, Callewaert said both he and his wife/business partner, Jane, teach their staff to get to know the other trades on the job. “Build a relationship,” he said. “Demonstrate respect. Ask what they need from us to make their job easier.

“We’re never too busy for the other trades involved,” he explained. “If they need our help to execute their job well, they’ve got it. Maybe they need to gain access to the space we are working in so they can finish. It might not be convenient, but because it helps them finish, we will figure it out. Respect goes both ways. When we need something from them, they are quick to accommodate.”

As Parker concluded, “we are currently working on filling that [trade] gap and getting everyone on the same page with wet area tile installations. When we all come together for a common goal (industry standards or above), there is a greater understanding and appreciation of everyone’s job.”

What fill should we use to withstand the weight of an 800 lb. clawfoot tub?

QUESTION

We have a customer that has terrazzo in their home. We removed the tub surround and a closet area and there was no terrazzo underneath it, so it is at least a 1-1/2″ drop down that we need to fill before installing floor tile on top. We will be installing a very heavy claw tub on top of the floor tile. What do you suggest we fill the hole with that can withstand the weight of the tub that is at least 800 lbs.? Concrete would have to cure and my customer is not willing to wait the 30 or 60 days unless it is the only solution. Is there anything else we can use?

ANSWER

I suggest that a thick bed (mud bed/dry pack) would be the best alternative to fill the void. Most require a 72-hour cure time at the longest. Some pre-mixed versions can be tiled over (or have membranes applied) sooner. If using a wet-bed method, it is tiled immediately.

Details for installing a thick-bed method can be found in the TCNA Handbook. Use the Method Locator for Ceramic Tile near the back of the book to locate the Floor methods then find the type of substructure (i.e. wood framing), and you will be directed to the page number(s) for the appropriate methods. 

To waterproof or not to waterproof, that is the question

The TCNA Handbook for Ceramic, Glass, and Stone Tile Installation highlights the building designer’s responsibility to know how each tile installation will be used and maintained, to avoid under-designing an area for the amount of water it will be exposed to. Courtesy of the Tile Council of North America, Inc. (TCNA).

I talk to many people who are not clear on when and where to use waterproofing under tile installations. The most surprising thing I come across is those who think that tile, grout, mortar and backer board are waterproof. Unfortunately, there are many failed installations due to the lack of waterproofing and improper waterproofing, so let’s look at when to consider using waterproofing under tile.

A good place to start is the Tile Council of North America (TCNA) Handbook, which addresses waterproofing in several places. There are specific sections such as the “Membrane Selection Guide” and the “Wet Area Guidelines” that discuss membrane usage. The Membrane Selection Guide outlines several different types of waterproofing, from non-metallic, lead, copper, CPE and PVC. There are also the ANSI A118.10 trowel-applied sheet or liquid waterproof membranes commonly familiar to the tile trades. Sometimes these are referred to as fluid-applied membranes. Once cured, these ANSI A118.10 membranes are designed to provide a continuous membrane that tile can be directly bonded to.

The Wet Area Guidelines section in the TCNA Handbook is a very useful for understanding the requirements for waterproof membranes. In addition to discussing the environmental exposure classification, this section also discusses proper slope required for wet areas, as well as the different types of drains, such as clamping drains and integrated bonding flange drains. One of the most important topics discussed in this section is performing the water test, commonly called a flood test or 24-hour test. Testing the ability for the area to properly hold water is an important factor to know prior to installing tile and is required by certain municipalities.

Many TCNA Handbook methods include the possible use of a membrane, leaving the design professional to determine whether one is needed, based on the expected water exposure.

Within the TCNA Handbook methods, such as F141-19, the diagram shows the option for a membrane and below the diagram it states, “*Use of a membrane is optional. See membrane options.” Does that mean a membrane usage is optional at the discretion of the installer? No, first, it’s important to understand the designed usage of the space and its Environmental Exposure Classification. The Environmental Exposure Classification section in the TCNA Handbook is often overlooked and yet it holds a wealth of information with regards to the intended usage of a space and thus the proper classification. These classifications are divided into two categories, residential (res) and commercial (com). Both the residential and commercial categories are further divided into seven separate classifications, each with its own expected water exposure.  

In the example TCNA F141-19, the area is designed with limited water exposure has a rating of Res1,2/Com1,2. If this space is going to be used as a commercial kitchen for instance, this area is typically designed with limited

Commercial kitchen maintenance practices vary widely. Some are routinely saturated during cleaning and require a membrane.

water exposure in mind, giving it a Com2 usage rating. The difference could be as simple as how the space is cleaned, do they intend to hose down the walls and floor? If so, the area would need to be designed for increased water exposure as outlined in the membrane options within the TCNA F141-19. Typically, in this type of situation, the flashing connections to the walls and any drains need to be addressed to create a complete waterproof system.

As you can see, there are a lot of considerations for the proper selection and use of waterproof membranes. If you have specific questions, contact a membrane manufacturer and they can help with the correct choice of material. Some manufacturers even provide job site support for the proper installation of their material. I’ll leave you with my simple rule of thumb, if it’s going to see water exposure, waterproof it – because in the end it’s cheaper than a failure.

What is the best product to use to install resin-backed stone?

QUESTION

What is the best product to use to install resin-backed stone?

ANSWER

Epoxy is the safest choice. You could do a bond test with thinset to see how well it will adhere. Simply install a piece over concrete or concrete board, allow it to dry, and then see how well it is stuck. Some mortar manufacturers are making mortars they claim will adhere to resin-backed stone. If you have a relationship with a representative or a mortar manufacturer, they may have something they will warranty with it. Contacting the stone provider is always your first course of action. If you don’t get answers or test it, use epoxy. 

Negotiate and draft “pass through” clauses you can live with

Owners, contractors, subcontractors and lower-tier contractors must have a sound understanding of the operational details and triggers of “pass-through” provisions as their terms can significantly impact the obligations and risks of performing for lower-tier contractors. 

What is a pass-through clause?

Pass-through clauses (a.k.a. flow-down or conduit clauses), typically incorporate by reference the terms of a prime contract between owner and general contractor into a subcontract, thereby binding subcontractors to the same duties and obligations – and to the same extent – as the general contractor has to the owner. Pass-through clauses may use general “substantially as follows” or “substantially the same as” language, but, importantly they are not uniformly worded and can have the effect of imposing obligations never negotiated or contemplated by the lower-tier contractor. However, when drafted and used correctly pass-through clauses can provide protections to all parties by unambiguously flowing down specific upstream obligations of general contractors to the subcontractors who are actually performing the majority of the work. 

How are pass-through clauses implemented? 

It is in the owner’s interest to bind the subcontractor to the same obligations as the general contractor. For the general contractor, pass-through clauses provide a way of ensuring that subcontractors, suppliers and other downstream parties are required to comply with certain prime contract requirements. 

However, subcontractors may attempt to reject responsibilities flowing down to them when the pass-through terms lack sufficient clarity as to the subcontractor’s specific contractual and compliance obligations. Subcontractors will want to limit or reject overly broad pass-through clauses which – for example – make them assume responsibilities meant for other parties or that incorrectly excuse a prime contractor for its mistakes while still flowing down the responsibility for the mistakes to subcontractors. 

Other pass-through clauses may require that subcontractors be paid by the general contractor when the general contractor is paid by the owner. In such a scenario, a savvy subcontractor will want to reduce the risk of non-payment by negotiating and re-drafting terms to avoid limiting the subcontractor’s rights or remedies in the event of a claim or payment dispute. 

Subcontractors and contractors should work collaboratively to negotiate, revise or remove pass-through clauses that are of concern or to re-balance the risks. 

There are many other scenarios to which pass-through clauses can apply and where their effectiveness depends upon how well all parties can agree on their interpretation, such as: 

  • Who has authority to approve a change order, claim or delay notification and in what form it should be submitted, detailed, and supported by documentation? 
  • Who will have the responsibility for prosecuting a claim against the owner and how the recovery and attorney’s fees will be allocated – whether arbitration or litigation – and which parties will be required or permitted to participate? 
  • What happens if there are pass-through claims of subcontractors (i.e., claims the owner is responsible for) and claims that are only between the general contractor and a subcontractor? 

Importance of properly drafted pass-through clauses

As the “pass-through” language in prime contracts and subcontracts tends to “flow-down” damages, limits of liability or indemnification downstream – from the owner and general contractor level to lower tiers of subcontractors and suppliers – pass-through clauses become no less important than any other terms in a construction contract. 

It is essential that drafters review the prime contract and the complete set of the upstream documents in order to craft effective pass-through provisions. Moreover, well-drafted pass-through provisions should only include terms that already exist in the prime contract; and should not flow down the entire prime contract because doing so introduces contradictions with other subcontract terms. 

To assist parties with drafting pass-through clauses, The American Institute of Architects (AIA), in its A201™–2017 provides subcontractual relations language, used in owner-general contractor agreements, by which contractors can require subcontractors to be bound to the contractors by the same prime contract terms and to assume toward the contractor all the obligations and responsibilities that the contractor assumed toward the owner. It also allows subcontractors the benefit of all rights and remedies against the contractor that the contractor – by the prime contract – has against the owner, and requires the contractor to identify to subcontractors any terms and conditions of the subcontract that may be at variance with the prime contract documents.

Similarly, the AIA’s language establishing the contractual relationship between contractor and subcontractor in the A401™–2017, which cross-references A201–2017, passes “the duties and responsibilities of the Contractor under the Prime Contract to the Subcontractor with respect to a portion of the work designated in the completed A401–2017 document.” 

The enforceability of pass-through clauses in complex construction agreements often hinges on the perceived clarity or ambiguity to both upstream and downstream parties. In order to avoid unintended legal or financial consequences the critical drafting process should be assisted by professionals experienced in commercial law and construction law and with accessibility to all of the upstream and downstream documents.

Pass-through interpretation and enforceability can vary by state

The location of the project plays a significant role in how pass-through language may be interpreted and enforced. Therefore it’s important to understand the nuances of applicable state laws when drafting and implementing pass-through clauses. 

For example, in New York, courts have held that general “incorporation clauses” in a subcontract can only bind a subcontractor to the “scope, quality and manner of the work to be performed by the subcontractor.” While many states take the New York approach, other states do allow a generalized “flow down” of obligations via “incorporation clauses.” And still other states construe all contract documents, including the prime contract, subcontract and all exhibits, together in an effort to harmonize and give effect to all of the provisions of the contract so that none will be rendered meaningless.

Pass-through best practices

Below are a few other examples of best practices that should be considered when reviewing or drafting pass-through provisions:

  • Negotiate pass-through terms at the pre-bid stage so that the costs/benefits of undertaking flowed-down obligations may be factored into bids. 
  • Parties should work collaboratively to address gaps in risk-shifting or risk-sharing and develop acceptable levels of risk. 
  • Limit the requests for pass-through revisions to a small group of terms or issues (and not to the prime terms) to increase acceptance. 
  • Avoid using general “incorporating by reference” language that can be misinterpreted to merely incorporate prime contract for a limited purpose. 

Toolbox Talks for Quarriers Available in Natural Stone University

Oberlin, OH, November 20, 2019—The Natural Stone Institute, in coordination with the National Building Granite Quarries Association (NBGQA), has added three toolbox talks for quarriers to the Natural Stone University. Topics include the following:

  • Fall Arrest System Regulations
  • Highwall Management and Use of Drones
  • Quarry Slab Tipping Safety

There are now a total of 27 quarry-specific toolbox talks available in the University, covering topics ranging from personal health and human safety to the safe use of equipment such as wire saws and preventing silicosis.

Natural Stone Institute Logo

The Natural Stone Institute, in coordination with the National Building Granite Quarries Association (NBGQA), has added three toolbox talks for quarriers to the Natural Stone University.

Mike Loflin, Industry Research & Information Manager for the Natural Stone Institute commented: “These quarry-specific resources are an important addition to our library of safety resources. The information provided is the cumulative work of the NBGQA safety committee. The NBGQA safety committee consists of some of the most talented safety officers, operations managers, and human resources professionals in the natural stone industry. Over the last several years, the committee has identified issues and provided seriously needed safety solutions for the quarry sector of the dimension stone industry. We are proud to partner with NBGQA to present these resources free of charge to the industry through the Natural Stone University.”

 

To access these toolbox talks and other educational resources, visit www.uofstone.org. To learn more about the National Building Granite Quarries Association, visit www.nbgqa.com.

 

 

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