Natural Grey Chalcedony with Sugar Quartz Druzy Cluster 95g

A flat, elongated slab with a strongly patterned face. The base is a dark slate blue-grey chalcedony, and over it a pale sugar quartz crust has spread in irregular islands with soft, lobed edges, some joined into long streaks, others sitting alone as pale blotches. The result is a mottled two-tone surface across the full 91mm length, cool grey against near-white, with a single small orange-brown iron stain near the middle. At 23mm thick the piece is slab-like and shows its pattern best face-on.

The patchy coverage happens when the later quartz crystallizes unevenly over the chalcedony below, leaving parts of the original surface bare, which is what gives each piece a pattern of its own. Bulgarian grey chalcedony with sugar quartz comes from the Rhodope volcanic rocks. Untreated. Hardness is 6.5 to 7 on the Mohs scale, and the flat form makes it easy to stand upright or lay flat in a case.

Natural grey chalcedony with sugar quartz druzy, Bulgaria, single piece.