Tag: limestone
How Do Gemstones Get Their Color?
How do gemstones get their color? A small cluster of transition metal elements plays a major role in determining the value of many popular...
CALYMENE celebra — The Pride of Wisconsin Fossils
By Joseph “PaleoJoe” Kchodl
The common Silurian trilobite, CALYMENE celebra, is easy to identify, mostly because of the rock it is found in, the color, and excellent...
Oklahoma’s Ornamented Trilobite
By Joseph "Paleo Joe" Kchodl
DICRANURUS elegantus is a very highly ornamented spiny Devonian trilobite species. It has very long and flowing genal, thoracic and...
Arizona’s Kartchner Caverns
Story and Photos by Bob Jones
It was a balmy day just 45 years ago in November, when two doughty spelunkers investigated a limestone sinkhole...
Zeolite Minerals: Chabazite
By Jim Brace-Thompson
Chabazite (sodium calcium aluminosilicate hydrate) has translucent cube-like pseudo-rhombohedral crystals that often are penetration-twinned and that may be colorless, white, or shades...
Eye on Epidote
By Jim Brace-Thompson
Calcium aluminum iron sorosilicate Ca2Al2(Fe3+, Al)Si3O12(OH)
Epidote is one terrific silicate mineral for display. It produces well-formed prismatic crystals that are long, slender, striated...
Socorro’s Mineral Cornucopia
Story and Photos by Mark Leatherman
Anytime a rockhounding club has the privilege of being able to go underground as part of an extended field...
Fun Facts Saturday: Geology and the Golden Gate Bridge
Editor's Note: This is a new column wherein we explore a history-making moment and its connection to geology.
By Antoinette Rahn
Eighty-six years ago today (Jan....
De Colores: Las Vigas Veracruz and Amatitlan
Editor's Note: This is one of 10 Mexican locales recognized for mineral production. View the rest of the list as part of an article...
