Milky quartz

String of Nubian beads
MFA# 1991.1130

Milky quartz

Description

A cloudy or translucent form of Quartz. Quartz loses its clarity and becomes cloudy due to the submicroscopic inclusions of air and water. Milky quartz was commonly used for pendants and vessels until the early Dynastic period in Egypt (Aston et al 2000).

Synonyms and Related Terms

hydrothermal quartz; milk quartz; snow quartz; cuarzo lechoso (Esp.); quartz laiteux (Fr.); quartzo leitoso (Port.); Milchquarz (Deut.); melkkwarts (Ned.)

Physical and Chemical Properties

• Trigonal crystal system.
• Low birefringence.
• Low thermal expansion.
• Fracture = conchoidal.
• Luster = vitreous to greasy.
• Streak = white.

Composition	SiO2
Mohs Hardness	7.0
Density	2.65 g/ml

Resources and Citations

• B.Aston, J.Harrell, I.Shaw, "Stone" in Ancient Egyptian Materials and Technology, P.Nicholson, I.Shaw (eds.), Cambridge University Press, 2000, p. 52.

• C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979

• Wikipedia: http://en.wikipedia.org/wiki/Milk_quartz (Accessed Sept. 14, 2005)