Idocrase. A mineral occurring in tetragonal crystals and also massive, of a brown to green color, rarely sulphur yellow or blue. It is a silicate of alumina and lime, with some iron and magnesia. It is common at Mt. Vesuvius.
“Two things are necessary to the life of pure faith. The first is, that we behold God alone, under all the imperfect coverings that conceal him; the second is, constantly to have our souls kept in a state of dependence.”
–Fenelon