The 4th part of the diagram in the original post didn't show up, so I'll put it here. Click to enlarge and get the nitty gritty details. Because you know you want the nitty gritty details!

Next topic. Here's what cross bedding looks like

Here are some images from porosity tests.

Experimental setup. The stones are sitting edge-wise in a pan of water, and left that way for 15 minutes.

White Macaubus - Fairly porous. Water wicked up into the stone.
NOTE - this doesn't mean the stone is a bad one! All it means is you need to seal it, and seal the edges too.

Infinity White - Less porous than Macaubus. Look at how water traveled up the diagonal crack. The crack is there because I broke the stone with a hammer.

Wild Sea - Water did not soak up into the stone beyond the depth of water it was sitting in. That surprised me because usually sandstones are more porous than quartzite, but not in this case. Wild Sea is what geologists call "well-cemented," which means that minerals have filled in the original pore spaces between sand grains.

Cool, eh? #ScienceRocks

Fascinating! Where does White Princess fit in this classification?

Oh Damn! Why didn't I get Taj Mahal

Karin-Mt

AMAZING! You are a wealth of knowledge and we are all so lucky to have your explanations. I have learned so much about rocks. Thank you.

~Boxer

Now I have to go find my sample piece of Taj Mahal and dunk it in water ...

I'll be back in 20 minutes!

The sample of my Taj Mahal slab passed the dunk test too. Just as well, because it was installed two weeks ago! I am still going to make sure that my GC seals the edges, and most importantly, the edges in the range area, before the range gets installed next week.

Karin, you rock!

I'm not sure about White Princess - it may not be a quartzite at all, as some people say its marble. Start with this article, which sorts out the quartzite/marble mislabeling problem. http://usenaturalstone.com/definitive-guide-quartzite/

In general, it's always a bit risky to go strictly by a stone's name, since the trade names are a little flexible. ;) That's why I like to help folks understand the properties of the stone, not just the name. The properties will always tell you what you need to know!

Thank you

"... since the trade names are a little flexible. ;)..."

Understatement. I and some other regulars could use a bit more of that ourselves. :)

Karin,
I have Azzurra Bay Quartzite. The fabricator made the mistake of sealing it prior to cutting, giving it 5 days to dry and then sealing it 3 times. I believe there is moisture trapped in the stone appearing as small dark spots. They came out yesterday with Akemi impregnating sealer stripper and said to give it some time to dry out. Will this help? Anything else to try? I’ve attached some photos

@karin Do you know anything about Patmos quartzite?

jhrycyna:

Don't hold your breath waiting for a response from Karin please. The natural stone industry pays her to shill for them, but all the money in the world can't make stones unsuitable for countertop use suitable for countertop use.

Karin needs to tell her Brazilian overlords that she's out of scientific and technical lipstick to put on their impoted pigs.

Perhapsthis is the article she claimed to be working on four years ago? It has the same illustrations as those here.

Karin, I challenge you to put your geologist brain to work coming up with a solution to the pervasive problems inherent in the quartzite aspect of the natural stone industry, posted here ad nauseum. The industry has ignored and poo-pooed these catastrophies long enough.

The more I read the more I think you’re right. Granite and marble have been around forever and quartzite just recently became an option due to to new resin treatments. Resin can help with stability but not porosity. My stone is porous and I think my fabricator was subpar, so frustrating

"The natural stone industry pays her to shill for them...Karin needs to tell her Brazilian overlords that she's out of scientific and technical lipstick to put on their impoted pigs...Karin, I challenge you to put your geologist brain to work coming up with a solution to the pervasive problems inherent in the quartzite aspect of the natural stone industry"

The irony is that in this very thread, Karin has written at length about quartzite and its properties, and has written numerous other posts about testing quartzites and what to watch out for. Apparently @Joseph Corlett, LLC wants Karin Kirk to solve all the problems of the stone industry.

@Joseph Corlett, LLC's comments above about Karin Kirk are despicable even for him who frequently tosses out supercilious comments on this forum. @Joseph Corlett, LLC - provide backup that Karin, as you put it, has "Brazilian overlords". Provide backup for your statement that "The natural stone industry pays her to shill for them". You are one to frequently talk of lawsuits on this forum. Yet here you are, fervently making libelous statements about Karin.

If Karin did not respond to the recent comments by @Lindsey Brady and @jmh0405, it could be because they have not actually tagged her, so how is she supposed to know she is being asked a question. Her tag is @karin_mt. Though with what Joseph Corlett wrote about her, I wouldn't blame her for not coming back to this forum. Karin Kirk has a website with her contact info if you want to look her up.

BTW, Karin holds a bachelors in geology from Skidmore College and a masters in Earth Sciences from Montana State University. She has taught courses about climate change, ran energy conservation projects, worked on national-scale climate education efforts, and worked with NOAA on its Climate.gov website. She also has a TED Talk on climate change if you are interested. (There are about 100,000 people that apply to give a TED Talk every year. 100 get selected.)

Karin does not dispute that she is paid to write friendly articles for the Natural Stone Industry.

"A shill, also called a plant or a stooge, is a person who publicly helps or gives credibility to a person or organization without disclosing that they have a close relationship with said person or organization."

Karen is a fine person and her contributions are appreciated. My concern is why a woman with such talent and resources at her disposal doesn't make solving the quartzite crisis, so thoroughly documented here, a priority. I speculate that the Brazilians importing this junk and their donations to the Natural Stone Institute, don't want this issue addressed and don't care if consumers and fabricators suffer. Clearly the NSI doesn't give a hoot.

I don't want her to "solve all the problems of the natural stone industry", but who is in a better position than her to lead the resolution of this very narrow particular problem?

@karin_mt is there any hope to remove these stains from my Azzurra Bay Quartzite Countertops? I think it's epoxy bleed at the seam and silicone from the under mount sink.

Wow, what a cool job, Karin! Congrats!!

@jmh0405 has there been any change since they stripped off the sealer? If not, then there might not be much hope for it. If the stains are limited to where the seam and the sink are, then that might be the cause, but I don't think those are very fixable, unfortunately.

@mxk3 z5b_MI - Thank you! It is pretty cool and I am grateful for the opportunity!

@karin_mt Thank you for your insight. They were installed on 2/15. They have tried to strip the sealer using Akemi Impregnating Sealer Stripper and came out last week with lacquer thinner. Still no change. He said he ordered some products and will try a poultice when it comes in.

I understand that my slab is porous but would expect it to be appropriately sealed on all edges and a non-bleeding adhesive used. If these stains cannot be removed what is a reasonable expectation of the fabricator and or distributor?

I think it's reasonable to have a stone that looks new and nice at the outset. How it holds up over time becomes more of a grey area where the customer bears some responsibility. But it sounds like you just had this installed? If so, and if this is a mistake caused by the wrong adhesive or the wrong sequence of events for cutting and sealing, those are fabricator errors. It's a bummer for them, but this isn't your fault. They should either make this stone right, or scrap it and provide a new one.

Any idea about Bianco Supreme? Is it quartzite? Is it porous?