175 ct. Montana 'Iris' Agate Slice
|Color: Light Brownish-Gray||Clarity: Translucent|
|Origin: Montana||Cut: Polished Slice|
|Treatments: None||Measurements: 94.3 x 36.1mm|
A remarkably interesting slice of American Agate. The stone is a virtual gemological landscape, the fine lines and swirls the consequence of the thin, botryoidal growth structure of the material. Quite fascinating is the effect seen when light is transmitted through the stone, the thin lamellae of agate will defract the light and create an iris effect. This is not a spectral color show, but rather a kind of moving glow - a curious thing to behold. A bit more on the structure of this material can be found in this article from American Mineralogist.