Über Tundra Grey
Castle Grey (also Castle Gray, Castle Grey Marble) is a grey natural marble marketed primarily by Chinese stone exporters. Available evidence suggests Turkish origin, with the stone also identified as Tundra Grey / Castle Grey from 'old quarry' sources. Medium to dark grey base with bold cloud-like movement -- interwoven veins of icy cream, light grey, white, and occasional rust/red lines. Distinctive among grey marbles for its dramatic visual pattern. SC s20582 (Castle Grey Marble) and SC s17870 (Castle Gray Marble) confirm the stone exists in trade. No DNSA entry, no manufacturer technical datasheet. Provisional record -- identity as Turkish grey marble is probable but not confirmed by primary quarry source.