Rainbow Calsilica is a rainbow colo

Rainbow Calsilica is a rainbow colored stone from Chihuahua, Mexico. It does not take a super high shine, which makes it a natural with casual clothing - especially jeans. It is right at home with dressier outfits as well and coordinates with a lot of colors. Although I tend to buy striped material, you will also see big, random patterns. It just depends on whether it is cut with the stripes or across the stripes.
Calsilica appears to be a natural stone, although there was controversy when it was first introduced to the market and that information still lingers. Testing was done by some labs, who determined that is was a natural stone. Testing was done by other labs, who determined that it was a man-made product. It is not clear though if the labs that declared it to be man-made were testing "out-of-the-ground" material or stabilized material. Until the mine owner decides to allow a geological expert trusted by the industry into the mine shown in photographs, the controversy will continue.
The greens and blues in the stones are calcite allophane clay. The other colors are silica tinted by trace metals to create reds, browns, tans, yellows, whites, etc. Calsilica is stabilized in the same manner as turquoise.
I don’t really care whether calsilica is a natural stone or turns out to be an elaborate hoax that is really a manmade product. The bottom line is that it is a fun stone that gets lots of comments