Steven Dutch, Natural and Applied Sciences, University
of Wisconsin - Green Bay
First-time Visitors: Please visit Site Map and Disclaimer.
Use "Back" to return here.
- Calcite, Dolomite, Siderite and other common carbonates are almost indistinguishable in
- Extremely high relief
- Colorless, but tends to be grainy in appearance. The extremely high relief means even
the tiniest irregularities stand out.
- Perfect rhombohedral cleavage
- Extremely high order interference colors. Has a pearly appearance because of tiny
patches of color. Even the slightest variation in thickness due to grinding
noticeable color variation.
- Twin bands are common (A). These often have moderate but highly mottled color because
the crystallographic orientation in the twin band partially cancels out the interference
color of the rest of the crystal. Calcite is extremely ductile and these are often due to
Calcite in plane polarized light.
In crossed polarizers, the interference colors are extremely high order and twin
lamellae are common.
The specimen below, seen in crossed polarizers, shows iridescent twin lamellae.
Return to Thin-Section Index
Return to Mineral Identification Tables
Return to Professor Dutch's Home Page
Created 22 Sept 1997, Last Update
14 Dec 2009
Not an official UW Green Bay site