Soapstone

Hardness of 1 on Mohs scale (can be scratched by fingernail), color is grayish-green with white inclusions, greasy or soapy feel, massive crystal structure (cryptocrystalline), dull to pearly luster.

Formed by the regional metamorphism of ultramafic rocks (like dunite or peridotite) or by the hydrothermal alteration of dolostone. It often occurs at convergent plate boundaries.

Commonly used for countertop surfaces, fireplace hearths, sculpture carving due to its softness, and historically for 'whiskey stones' because of its high heat capacity.

Soapstone is exceptionally heat resistant and non-porous, making it one of the few rocks that will not stain and can withstand direct flame without cracking. It has been used for thousands of years by indigenous cultures to carve bowls and ornaments.

Identify by its characteristic 'greasy' feel and extreme softness (scratches easily). Commonly found in the Appalachian mountains (USA), Brazil, and Scandinavia. Pieces cut into cubes are often sold as reusable ice cubes (whiskey stones).