Hardness: 6.00-6.50
Refractive Index: 1.56-1.57
Specific Gravity: 2.55-2.76
Birthstone:
Astral Stone:
Anniversary Stone:
Origination: Worldwide. Feldspars cover approximately 50% of the earth's crust. Concentrations occur in Africa, the United States, Finland, Russia, Canada and others.
Care & Cleaning: Varies from one variety to another. Some feldspars are fragile. When in doubt, a soft polishing cloth is always your best choice.
Fiction, Facts & Folklore:
Actually, "Feldspar" is the group name for any number of gems in one fairly large family. These include Moonstone, Spectrolite and Labradorite.
Both Moonstone & Labradorite are considered gems of the winter. That probably has something to do with their location in very cold weather climates, but personally, I have no intention of ever finding out for sure.
If your name happens to be Ferdinand, Feldspar is your namesake stone.
For additional information, please see Moonstone, Spectrolite, Labradorite, Sunstone and Orthoclase, all important members of the Feldspar mineral group.