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nist-gov/www.nist.gov/blogs/taking-measure/test-time-nists-wall-many-stones
Scott Williams 4063bef310 Initital commit.
2025-03-05 18:59:57 +00:00

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<h1 class="nist-page__title">The Test of Time: NIST’s Wall of Many Stones</h1>
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<div class="daterange"><time datetime="2018-01-16T12:00:00Z">January 16, 2018</time>
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<span>By: </span>
<a href="/blogs/taking-measure/authors/jason-stoughton" hreflang="en">Jason Stoughton</a>
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<figure class="nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_wall.jpg?itok=VHgRbV1C" data-media-id="418111">
<img loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_wall.jpg?itok=sG4CEgQZ" width="960" height="600" alt="NIST stone wall weathering experiment" typeof="foaf:Image" />
<figcaption class="nist-image__caption">
<div data-caption-editable="true" class="nist-image__caption-content">
<p>NIST’s stone test wall, just after a summer rain.</p>
</div>
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div>
</figcaption>
</figure>
<p>Frequented by more deer than people, the NIST stone test wall lives a fairly isolated existence. Out among the trees and the grass on&nbsp;<a href="https://www.google.com/maps/place/39%C2%B007&amp;apos;20.8%22N+77%C2%B013&amp;apos;14.8%22W/@39.122456,-77.2213112,314m/data=!3m2!1e3!4b1!4m14!1m7!3m6!1s0x0:0x0!2zMznCsDA3JzIwLjkiTiA3N8KwMTMnMTQuNyJX!3b1!8m2!3d39.1224722!4d-77.22075!3m5!1s0x0:0x0!7e2!8m2!3d39.1224558!4d-77.2207636">the south end of the Gaithersburg, Maryland, campus</a>, it cuts an imposing and visually bizarre figure. Set in the mortar of its technicolor face are more than 2,000 square and rectangular stone samples showing off practically every naturally occurring type and color of stone. Nearly 70 years old, it is the world’s longest-running weathering experiment for stone samples, as well as a reminder of the symbiotic relationship between science and industry.</p><p>Over the past 70 years, the stone test wall has served as a sort of check against so-called “rapid-weathering” tests conducted in laboratories. Builders want to know if the stone they select today will still be strong and visually appealing decades into the future. With rapid-weathering tests, a piece of stone can be subjected to years’ worth of abuse meted out by factors like sunlight, temperature changes and moisture, in just a matter of weeks. And although rapid-weathering is highly efficient and an industry standard, the stone test wall is the real deal. If you want to see what&nbsp;<em>actually</em>&nbsp;happens to a particular piece of stone after it’s been exposed to the elements over decades, NIST’s stone test wall stands ready and waiting to show you.</p><p>&nbsp;</p>
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_wall_pa_slate.jpg?itok=XtZXfPsM" data-media-id="418116">
<img alt="Severely weathered sample of Pennsylvania slate in the NIST Stone Wall" height="2000" loading="lazy" src="/sites/default/files/images/2018/01/11/nist_stone_wall_pa_slate.jpg" typeof="foaf:Image" width="3000">
</div>
<figcaption class="nist-image__caption">The worse for wear: one of many striking stone samples on the wall. This one is slate from, appropriately, Slatington, Pennsylvania.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
<p>The current location of the stone test wall is on a secluded hill on NIST’s Gaithersburg campus. Despite the wall’s massive size and weight, Gaithersburg is actually its second home. It was originally constructed in 1948 on NIST’s original campus (then the National Bureau of Standards) in Northwest Washington, D.C. In 1976 the wall was moved to its present home in Gaithersburg and there it remains.</p><p>However, the story of the wall and why it was originally constructed, not to mention where all those stone samples came from, goes back over 140 years to when America was celebrating its 100th&nbsp;birthday.</p><h3><strong>Buy American</strong></h3><p>In the late 1800s, the industrialization and expansion of many American cities had created a boom in the construction industry. While many of those nice new buildings required stone for their construction, stone quarried domestically in the U.S. was oftentimes shunned by builders in favor of stone from older, more established sources outside the U.S. For example,&nbsp;<a href="https://books.google.com/books?id=ASefBnc3f3YC&amp;dq">an 1884 Department of the Interior report on petroleum, coke, and building stones</a>&nbsp;notes that local stone from California was not trusted, and that “The first stone house erected in San Francisco, for example, was built of stone brought from China.”</p><p>Like any business trying to gain more customers, the U.S. stone industry naturally wanted to promote its products. And a perfect opportunity soon presented itself.</p><p>The first official world’s fair held in the U.S. was the Centennial International Exhibition of 1876 in Philadelphia. This wide-ranging event was not only a blowout celebration of the country’s 100th&nbsp;birthday but also a showcase for American-made goods and inventions. The exhibition featured an array of futuristic, newfangled products, like a steam-powered monorail, Alexander Graham Bell's first telephone, and Heinz ketchup.</p><p>Among the many exhibits in Philadelphia was an impressively diverse collection of stone samples, all quarried from states and territories across the relatively young U.S. of A.</p><p>&nbsp;</p>
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_wall_variety.jpg?itok=zhU2qhcR" data-media-id="418121">
<img alt="Seventy stones from the NIST Stone Test Wall" height="2000" loading="lazy" src="/sites/default/files/images/2018/01/11/nist_stone_wall_variety.jpg" typeof="foaf:Image" width="3000">
</div>
<figcaption class="nist-image__caption">A small sample of the variety of stone contained in the wall. The wall holds 2,352 individual stone samples. This picture only shows about 70.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
<h3><strong>Made to last (or not)</strong></h3><p>After the party in Philly wrapped up, the stone samples were eventually grouped into two large collections. One collection was shipped to Columbia University and the other to Washington, D.C.’s newly established National Museum, which later became the Smithsonian’s Arts and Industries Building.</p><p>But the Smithsonian’s newly acquired collection was still just a large grouping of loose stones, albeit one of fantastic variety. The stones would not be joined together in a wall until several decades later when the Smithsonian turned over its part of the collection to NIST in the early 1940s. The unique nature of the collection was not lost on building experts of the time. They recommended that a test wall be constructed from the many different stone samples to study long-term weathering in a consistent way.</p><p>The wall was eventually constructed in 1948, after World War II (NIST, like many other U.S. agencies, was highly involved in the war effort, and studying long-term weathering was a slightly lower priority than defeating the Axis powers). NIST combined the original stone samples with additional samples collected from other sources. In total, the finished wall contained 2,352 individual stone samples, quarried from 47 U.S. states and 16 foreign countries.</p><p>Even the mortar holding the stones was purposefully selected for testing, with the entire right half of the wall set in high-calcium lime mortar, while the left half was set in portland cement mortar. And every single stone sample was meticulously set by one mason, Vincent Di Benedeto, working all by himself.</p><p class="grid-row grid-gap">&nbsp;</p>
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/di_benedeto_nist_stone_test_wall_mortar_work.jpg?itok=23hKDSLx" data-media-id="418131">
<img alt="NIST Stone Test Wall mortar work" height="2000" loading="lazy" src="/sites/default/files/images/2018/01/11/di_benedeto_nist_stone_test_wall_mortar_work.jpg" typeof="foaf:Image" width="3000">
</div>
<figcaption class="nist-image__caption">Some of Mr. Di Benedeto’s meticulous handiwork.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
<p class="grid-row grid-gap">The finished wall stood in Washington, D.C., weathering away, for the next few decades. But the stones would be moved yet again. A year after America celebrated its bicentennial, the entire wall was moved—intact—and installed on the Gaithersburg campus in 1977, just over 100 years after the stone samples had originally been exhibited in Philadelphia.</p><h3><strong>Every type and color</strong></h3><p>The photos below show just a few picturesque examples of the wall’s many stone inhabitants.</p><p>Although many of the samples in the wall are rarely, if ever, used in buildings, some are quite popular. Indiana limestone and Potomac marble, used in buildings like the <a href="https://www.aoc.gov/us-capitol-building">U.S. Capitol</a>, are both present in the wall. Some of the wall’s other well-known residents include the Tennessee marble of the <a href="https://www.nga.gov/about.html">National Gallery of Art</a>; marbles from Maryland&nbsp;and Massachusetts used in the <a href="https://www.nps.gov/wamo/learn/historyculture/index.htm">Washington Monument</a>; Colorado marble used for the <a href="https://www.nps.gov/linc/learn/historyculture/memorial-features.htm">Lincoln Memorial</a>;&nbsp;and Mount Airy granite from North Carolina used in the <a href="https://www.nps.gov/gwmp/planyourvisit/memorialave.htm">Arlington Memorial Bridge</a>.</p><p>It's truly a rock wall for the ages, and, with any luck, it will stand for ages to come.</p><div class="grid-row grid-gap"><div class="grid-col">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_ohio_sandstone.jpg?itok=4bOl1PBI" data-media-id="418136">
<img alt="NIST Stone Test Wall Ohio yellow sandstone with loose stone" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_ohio_sandstone.jpg?itok=67LOKDVY" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">Time has not been kind to this sandstone from Cumberland, Ohio. A loose nugget sits in the weathered pocket.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div><div class="grid-col last">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_ohio_sandstone_nugget_detail.jpg?itok=mpOswNlY" data-media-id="418146">
<img alt="NIST Stone Test Wall Ohio sandstone detail of loose nugget sitting in weathered pocket" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_ohio_sandstone_nugget_detail.jpg?itok=_BdPHwvA" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">A close-up of the sandstone nugget.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div></div><div class="grid-row grid-gap"><div class="grid-col">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_portuguese_yellow_marble.jpg?itok=KErH0XdH" data-media-id="418161">
<img alt="A fine-grained yellowish marble from Coimbra, Portugal, in the NIST Stine Test Wall" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_portuguese_yellow_marble.jpg?itok=E1j2n49P" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">A fine-grained yellowish marble from Coimbra, Portugal.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div><div class="grid-col last">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_portuguese_yellow_marble_fissures_detail.jpg?itok=af60NxLJ" data-media-id="418166">
<img alt="NIST Stone Test Wall Portuguese yellow marble fissures detail" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_portuguese_yellow_marble_fissures_detail.jpg?itok=0MUZA0F2" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">A close-up of fissures in the Portuguese marble.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div></div><p>&nbsp;</p><div class="grid-row grid-gap"><div class="grid-col">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_light_red_colorado_limestone.jpg?itok=KH9Zkj_A" data-media-id="418176">
<img alt="NIST Stone Test Wall light red Colorado limestone" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_light_red_colorado_limestone.jpg?itok=89M3Ff4C" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">Light red limestone from Morrison, Colorado.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div><div class="grid-col last">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_north_carolina_coarse_limestone.jpg?itok=SSE9YtyK" data-media-id="418181">
<img alt="NIST Stone Test Wall North Carolina coarse limestone" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_north_carolina_coarse_limestone.jpg?itok=q0ISUyVK" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">Coarse limestone from New Bern, North Carolina.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div></div><div class="grid-row grid-gap"><div class="grid-col">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_michigan_red_and_grey_sandstone.jpg?itok=_O5Qz05Q" data-media-id="418186">
<img alt="Asteroid-like landscape formed of red and gray sandstone from Marquette, Michigan" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_michigan_red_and_grey_sandstone.jpg?itok=MEAQnIvb" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">A miniature, asteroid-like landscape formed of red and gray sandstone from Marquette, Michigan.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div><div class="grid-col last">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_new_jersey_orange_and_green_granite_and_purple_conglomerate.jpg?itok=xcZqDqg_" data-media-id="418191">
<img alt="NIST Stone Test Wall New Jersey orange and green granite and purple conglomerate" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_new_jersey_orange_and_green_granite_and_purple_conglomerate.jpg?itok=JXMYkRuz" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">On the left, orange and green granite from Pompton Junction, New Jersey, also known as “Pompton Pink.” On the right, from Morristown, New Jersey, reddish-purple conglomerate. In the middle, the portland cement mortar that holds all the stones on the left side of the wall.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div></div><div class="grid-row grid-gap"><div class="grid-col">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_mexican_black_basalt.jpg?itok=ZxX0dbH4" data-media-id="418201">
<img alt="NIST Stone Test Wall Mexican black basalt" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_mexican_black_basalt.jpg?itok=80HY7-KY" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">Black basalt from the state of Puebla in Mexico.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div><div class="grid-col last">
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_austrian_marble.jpg?itok=29D0_1hc" data-media-id="418206">
<img alt="Fossil-filled marble from Salzburg, Austria" height="640" loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2018/01/11/nist_stone_test_wall_austrian_marble.jpg?itok=5WtQ0_J5" typeof="foaf:Image" width="960">
</div>
<figcaption class="nist-image__caption">Fossil-filled marble from Salzburg, Austria.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
</div></div><p>&nbsp;</p>
<figure class=" align-center nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2018/01/11/nist_stone_test_wall_under_the_stars.jpg?itok=CMAlyVvg" data-media-id="418211">
<img alt="The NIST stone test wall under the stars" height="2000" loading="lazy" src="/sites/default/files/images/2018/01/11/nist_stone_test_wall_under_the_stars.jpg" typeof="foaf:Image" width="3000">
</div>
<figcaption class="nist-image__caption">The NIST stone test wall under the stars.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
J. Stoughton/NIST
</div></figcaption>
</figure>
<p><a href="http://stonewall.nist.gov/">Want to see stones from your state? Check out the searchable NIST Stone Test Wall website.</a></p>
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<a href="/blogs/taking-measure/categories/248371">Buildings and Construction</a>,
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<div class="text-with-summary"><p>In addition to being an unabashed science fanboy, Jason Stoughton is a writer, photographer, video producer and former director of NIST internal communications (now working at the National Science Foundation). Before coming to NIST he worked in broadcast television and video production in a variety of roles from creative director to night shift dub room technician, somehow winning 11 Emmy awards in the process. He lives in Silver Spring, Maryland, with his wife and daughter.</p></div>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">TaylorSun</span></span>
on
<span class="nist-comment__date">January 16, 2018 8:59 PM</span>
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<div class="text-long"><p>A touching paper, thanks Jason.<br />
Time flies, the experimant fairly isolated, but keep existence.</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">ryanfreeman</span></span>
on
<span class="nist-comment__date">October 29, 2021 11:34 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1635521906"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/60011#comment-60011" class="permalink" rel="bookmark" hreflang="en">A touching paper, thanks</a></span>
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<div class="text-long"><p>what is a rock</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Edwin Fuller, Jr.</span></span>
on
<span class="nist-comment__date">January 17, 2018 2:06 PM</span>
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<div class="text-long"><p>Thanks for the very nice article of the Wall. Even though I worked at NBS-NIST, I first learned of and was first shown the Wall by a visiting German guest scientist many years ago. I enjoyed the article and learning more about the Wall. At one time, NIST maintained a “twin” set of unexposed samples. Do you know if they still maintained?</p>
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<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Jason Stoughton</span></span>
on
<span class="nist-comment__date">January 18, 2018 10:20 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1516288840"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/60071#comment-60071" class="permalink" rel="bookmark" hreflang="en">Thanks for the very nice</a></span>
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<div class="text-long"><p>Yes, in fact you can find photos of many of the &#039;archival&#039; stones on the stone test wall website: <a href="http://stonewall.nist.gov/">http://stonewall.nist.gov/</a><br />
For example, here&#039;s the Cumberland, Ohio sandstone pictured in the article along with its archival &#039;twin&#039;:<br />
<a href="http://stonewall.nist.gov/asp/Z1_stonedescription.asp?page=A4_stonedescription_state.asp?result=Sandstone&amp;resultnumber=5RB7&amp;stateTrans=Ohio">http://stonewall.nist.gov/asp/Z1_stonedescription.asp?page=A4_stonedesc…</a></p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Paul Stutzman</span></span>
on
<span class="nist-comment__date">January 19, 2018 12:29 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1516382965"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/60071#comment-60071" class="permalink" rel="bookmark" hreflang="en">Thanks for the very nice</a></span>
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<div class="text-long"><p>Ed,<br />
The stonewall.nist.gov site shows the archive specimens with the exposed specimen. I have the archive specimens in cabinets in the lab for safekeeping. Your wall tour guide may have been Erhard Winkler, a geologist from Notre Dame University and expert in stone weathering. He visited in the late 1970&#039;s to catalog the stones and make some weathering depth measurements after about 30 years exposure.</p>
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<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Ed Fuller</span></span>
on
<span class="nist-comment__date">January 27, 2018 12:03 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1517029417"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/60426#comment-60426" class="permalink" rel="bookmark" hreflang="en">Ed,</a></span>
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<div class="text-long"><p>Thanks Paul,<br />
It is good to know the archive specimens are maintained. My guide was Thomas Weiss, a researcher from the geology department at Universität Göttingen. I know of Prof. Winkler by representation and his papers.<br />
All the best, Ed</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Colleen Hughes</span></span>
on
<span class="nist-comment__date">March 23, 2018 4:59 PM</span>
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<div class="text-long"><p>Poetic!</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Joe Hannibal</span></span>
on
<span class="nist-comment__date">March 1, 2019 1:43 PM</span>
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<div class="text-long"><p>There is much much more to be said. The collection that these stones were part of was a world class collection, but it grew out of fashion.</p>
<p>The collection, not only but including the wall, is important for provenance as well as for weathering. The last time I tried to examine one of the specimens that was supposed to be in a museum, it was missing.</p>
<p>It is important that museums and institutions preserve these materials.</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">John</span></span>
on
<span class="nist-comment__date">October 29, 2021 11:29 AM</span>
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<div class="text-long"><p>It&#039;s quite a good blog but it needs more pzaz</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">John</span></span>
on
<span class="nist-comment__date">October 29, 2021 11:30 AM</span>
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<div class="text-long"><p>Very good I love it a lot!</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Thomas Vitanza</span></span>
on
<span class="nist-comment__date">March 8, 2022 4:05 PM</span>
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<div class="text-long"><p>Is Paul Stutzman still with NIST? Who can answer questions about the wall? Many Thanks.</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Robin M</span></span>
on
<span class="nist-comment__date">March 23, 2022 3:26 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1648063663"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/106456#comment-106456" class="permalink" rel="bookmark" hreflang="en">Is Paul Stutzman still with…</a></span>
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<div class="text-long"><p>The wall currently is maintained by the Materials and Structural Systems Division within the Engineering Laboratory within the Infrastructure Materials Group. The group leader for that group is Aron Newman.</p>
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<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Smilewei</span></span>
on
<span class="nist-comment__date">June 7, 2023 9:51 PM</span>
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<div class="text-long"><p>Sorry to see this post so late. I&#039;m at a loss for words now. It&#039;s so beautiful.</p>
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