Description
Lapis lazuli is a rock, largely formed from the mineral lazurite.
The main component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral with the formula (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2. Most lapis lazuli also contains calcite (white), sodalite (blue), and pyrite (metallic yellow). Other possible constituents: augite; diopside; enstatite; mica; hauynite; hornblende, and nosean. Some lapis lazuli contains trace amounts of the sulfur-rich löllingite variety geyerite.
Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism.
Read more about this topic: Lapis Lazuli
Famous quotes containing the word description:
“Whose are the truly labored sentences? From the weak and flimsy periods of the politician and literary man, we are glad to turn even to the description of work, the simple record of the months labor in the farmers almanac, to restore our tone and spirits.”
—Henry David Thoreau (18171862)
“To give an accurate description of what has never occurred is not merely the proper occupation of the historian, but the inalienable privilege of any man of parts and culture.”
—Oscar Wilde (18541900)
“An intentional object is given by a word or a phrase which gives a description under which.”
—Gertrude Elizabeth Margaret Anscombe (b. 1919)