Sanidine

Felspar is a mineral not ususally known for fine collector gem crystals, but at this locality in Madagascar, amazing water clear crystals are sometimes found. This is a double-terminated crystal in excellent condition (I found 1 small chip and a bit of matrix attached to the bottom face), crystallized on all sides. The crystal has a good yellow coloration and is internally transparent. The faces alternate from smooth and glassy to a curvy surface texture that is common to these and always reminds me of a topographic map. There is a natural hollow area that extends into part of the back face. Weighs 43.47 grams.