Moonstone. A nearly pellucid variety of feldspar, showing pearly or opaline reflections from within. The best specimens come from Ceylon. Their value is not much more than the expense of cutting.
“See a flame in a spark, a tree in a seed; see great things in little beginnings; look not so much to the beginning, as to the perfection, and so we shall be in some degree joyful, and thankful unto Christ.”
–Richard Sibbes, The Bruised Reed and Smoking Flax