207.7 Gram 3-1/2" Glassy Flower of BLUE BARITE Crystals Cluster, Cavnic Romania

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  • Item Category: Natural History
  • Source: eBay
  • Sold Date: Apr 18, 2016
  • Channel: Auction House

Barite crystals occur in clusters attached to the walls of big pockets in brecciated rock. Between the pockets and the tunnels, the vertical walls of the small ravine where they are found look like Swiss cheese today. The insides of the pockets are coated with black iron oxides, and not all pockets host barite crystals. In addition, the color, size and luster of the crystals vary widely between different pockets.

The largest clusters are up to 8", and sit on either a reddish brown gossan matrix or the black iron oxide. The finest specimens look like radiating groups of flower petals. Individual blue barite bladed crystals can be up to 6", and they taper toward the terminations then come to a slightly rounded sword blade tip with a shallow point. Crystals are typically thicker in the middle, and taper toward the edges, which can be transparent. On the best pieces the crystals are translucent to almost transparent, with good luster. The color ranges from opaque white to a vivid blue; some of the crystals have hematite or limonite inclusions which tint the crystals brown to red brown.

The vast majority of specimens have one or more broken crystals, mostly due to unskilled extraction, but also the result of Barite's propensity to cleave across the width of the crystal. A fraction of the specimens are really spectacular,
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