Rainbow calsilica is a unique material that first made its appearance onto the world's stage at the Tucson Rock and Mineral Show in 2002. It quickly attracted huge amounts of attention from mineral collectors and enthusiasts from around the world but the one burning question that everyone was asking was is it completely natural?
The world's only supplier claimed that he imported rainbow calsilica from the state of Chihuahua in Mexico and it was a completely natural rock but people were not convinced. After countless questions and a great deal of speculation, geologists asked for access to the mine but the request was declined because it was claimed the owners of the land where the mine is situated want to protect the stone from exploitation.
An initial inspection of rainbow calsilica led some experts to believe it was a cryptocrystalline calcite with various clay minerals that were acting as bonding agents but another group of geologists who examined the stone said it was a man-made material that had been coloured with synthetic colouring agents. The supplier claimed he imported it in large slabs directly from the mine and it was then stabilised with an epoxy in order to increase its durability and that's what's likely to be showing up in the tests. Rocks and minerals are often stabilised in order to prevent them from eroding or crumbling and the process involves filling holes and gaps with a resin or other substance. The process may also be used to repair rocks and minerals so they can be cut as gemstones or used for other lapidary purposes.
Despite growing speculation over its authenticity, the world's only supplier of rainbow calsilica continued to deny anyone access to the mine and the story about the land owners wanting to protect it from exploitation just didn't ring true. Were it to be a naturally occuring stone it would have been an incredible discovery with the potential to make the people behind it extremely rich so the secrecy made no sense at all.
As the supply of rainbow calsilica increased it began popping up at mineral fairs around the world and was quckly becoming a highly sought after material. When the stone finally fell into the hands of a group of scientists the truth about it began to emerge. Having inspected a number of samples they concluded that man-made colouring pigments had been found in some of the layers along with the minerals hematite, celestine and calcite. They also revealed that many of the particles seemed to be bonded together using a soft plastic-like material that was similar to paraffin wax.
Rainbow calsilica appeared out of the blue and had baffled many, it attracted huge amounts of attention yet nobody has ever discovered who was behind its creation and mass production.
Whilst many articles online now confirm that the stone is synthetic, some continue to market rainbow calsilica as a natural rock that's mined in Mexico. The story behind it is both curious and fascinating and its creation whoever was behind it, was certainly an ingenious idea.