igneous
Preseli Bluestone
Dolerite ( Spotted Dolerite )
AI-generated identification · may be incorrectHardness of 6-7 on the Mohs scale, dark greenish-grey color with distinctive white or pale blue-white rounded spots, sub-vitreous luster, and dense aphanitic to fine-grained crystalline structure.
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Physical properties
Hardness of 6-7 on the Mohs scale, dark greenish-grey color with distinctive white or pale blue-white rounded spots, sub-vitreous luster, and dense aphanitic to fine-grained crystalline structure.
Formation & geological history
Formed from cooled and solidified magic magma intrusions approximately 480 million years ago during the Ordovician period in Wales.
Uses & applications
Used primarily in lapidary arts, metaphysical crystal healing, and famously as the inner circle megaliths at Stonehenge.
Geological facts
This specific spotted dolerite was transported over 250 miles from the Preseli Hills in Pembrokeshire, Wales, to build Stonehenge.
Field identification & locations
Identifiable by its contrasting white feldspar spots within a dark matrix; found primarily in southwest Wales.
