This rainbow calsilica (cal silica) pendant is handcrafted from 14K/20 gold filled wire and a rainbow calsilica cabochon (cab) from Mexico. I like calsilica. It gets a lot of comments when I wear it. It coordinates well with a lot of different colors. Although it looks good with dressy outfits, it also dresses down well to go with casual clothes and jeans. This one has a sparkle here and there as it moves. I believe it is due to small embedded crystals. 14K/20 gold filled wire is basically a tube of 14K gold with a jeweler’s wire down the center for flexibility. It wears well, does not tarnish, and has the same allergy reactions (or non-reactions) as 14K gold. Each of my cabochon pendants are "one-of-a-kind" and you are selecting the actual one you will be receiving. The chain is not included, but I do have a selection of chains if you need one. approximately 1 1/8" x 2 1/4" 28mm x 58mm 9mm bail