Mineral Specific Gravity Calculator

Identifying minerals without measuring volume directly

Specific gravity is one of the most useful diagnostic properties in mineral identification, and the hydrostatic weighing method lets you find it without needing to measure an irregularly shaped mineral's volume geometrically.

Worked example

For a mineral sample weighing 50g in air and 32g when submerged in water:

SG = 50 / (50 - 32) = 2.778

Mineral	Typical Specific Gravity
Quartz	2.65
Feldspar	2.55 - 2.76
Pyrite	4.9 - 5.2
Galena	7.4 - 7.6

The weight loss in water equals the weight of water displaced by the mineral's volume (Archimedes' principle), which is what makes this simple two-measurement technique work without any direct volume measurement at all.