This is a polished specimen featuring dark blue to black, dark golden yellow, and translucent gray agate with a large opening appearing to come from a flow channel. It has a "tube" which could be a partially closed second chamber.
12 cm x 16.5 cm x 2.5 cm
2 lb 14.8 oz
Polyhedroid Agates were found in Paraiba, Brazil, but are now unavailable. They are pseudomorphic formation of agate, forming in the negative space between large crystals of calcite or aragonite. They uniquely feature naturally flat surfaces in a variety of angles.
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