There are a mine in Germany as well. The soil improvement product from that mine is called seramis. I am sure it is used in products for sanitizing and kitten litter as well, however, I don't know any brand names.
But You are in USA Ivan. Sending soil components from Europe to America is just as bad idea as sending akadama from Japan to Europe. Go look for what components is mined locally. I know Nigel Saunders in Canada using an absorbent called safetysorb. That may be your local version?
At the moment, not an issue for me. I have months, and I have enough expanded shale to do about half of next year, but I will need more.
I have no more desire to ship clay here from Denmark than I want to ship clay here from Japan. Kitty litter seems to be available here in large bags, so I might try that if I can find the right type, which should be doable.
What does the "molar" mean in "molar clay"? That sounds like a chemistry word.
I started to type "molar clay" into Google and it completed it for me - "molar clay kitty litter" and there were several answers. I will look for some of them in local pet stores. The friendly person at checkout will ask what kind of cats I have, and I will say, "Three maples, a gingko, several elms, and a lot of azaleas." That will get me a look.