Agate
Image: Dave Dyet <a rel="nofollow" class="external free" href="http://www.shutterstone.com">http://www.shutterstone.com</a> <a rel="nofollow" class="external free" href="http://www.dyet.com">http://www.dyet.com</a> (Public domain)
Mineral NameAgate
Chemical FormulaSiO2
Mohs Hardness6.5
Crystal Systemtrigonal
Streak ColorWhite
CleavageNone
FractureConchoidal to uneven
Specific Gravity2.6
Colorsred, orange, yellow, brown, white, grey, black, multicolored
TransparencyTranslucent to opaque
Type LocalityBrazil, Uruguay, Mexico, Madagascar, USA
Mineral GroupSilicates
Usesjewelry, ornamental objects, carvings, collector specimens
Associated Mineralsquartz, opal, calcite, zeolites
Raritycommon
Description
A collection of polished agate cabochons, showcasing diverse patterns and colors, including orbicular (Ocean Jasper-like), banded, and translucent solid hues such as red (Carnelian) and yellow.
Geological Context
Agate forms in cavities of volcanic rocks (like basalt) and sometimes in sedimentary rocks, deposited from silica-rich hydrothermal solutions, often displaying concentric banding or other intricate patterns.
