PorphyroclastBy Bernardo Cesare

A porphyroclast is a crystal that is intensely deformed during the metmorphism of rocks. Here we see an orange colored porphyroclast of feldspar in a charoite-bearing rock. Charoite is a lovely purple-lavender mineral, quite rare because it has only been found in a locality from Siberia (Russia). As a semiprecious stone it is extensively used for lapidary arts.