I had never heard of tigrina before we found these in Tucson, and it’s been interesting trying to figure out what it really is. Some sources say that tigrina is a combination of tiger’s eye and pietersite, but pietersite itself is a combination of gold tiger’s eye and blue quartz in matrix, and it’s also known as brecciate tiger’s eye. Brecciated basically means that something is composed of angular fragments filled with a matrix of smaller particles and a mineral cement that binds the rock together. What gives pietersite its swirly nature is the formation of crocidolite inclusions within that matrix. In what we usually see as tiger’s eye, the same inclusions are arranged in lines and lend that stripy look.
We have a bunch of these and they’re all different–but they’re all amazing and really gemmy. A few show the “tininess” of tiger’s eye, some have more matrix, and one or two are mostly blue. They’re all $20 and will be popping up in our Etsy shop.