sedimentary

Wallboard/Drywall (Gypsum-based)

Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O

AI-generated identification · may be incorrect

Hardness: 2 (Mohs scale), Color: White/Light Gray, Luster: Pearly to dull when processed, Crystal Structure: Monoclinic (in mineral form), Cleavage: Perfect in one direction, Specific Gravity: 2.3

Identified March 22, 2026More sedimentary →

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Physical properties

Hardness: 2 (Mohs scale), Color: White/Light Gray, Luster: Pearly to dull when processed, Crystal Structure: Monoclinic (in mineral form), Cleavage: Perfect in one direction, Specific Gravity: 2.3

Formation & geological history

Formed as an evaporite mineral through the evaporation of seawater in marine basins. Modern wallboard is manufactured by dehydrating gypsum into plaster and sandwiching it between paper layers. Geological age varies by source deposit (often Permian or Triassic).

Uses & applications

Primarily used in construction for interior walls and ceilings. It is also used in fertilizer to provide calcium and sulfur to soil.

Geological facts

Gypsum is the most common sulfate mineral. It has a unique property where it can be dehydrated and rehydrated easily, allowing it to be molded into various shapes.

Field identification & locations

In a domestic setting, can be identified by its distinctive layered construction (paper/plaster/paper) and soft, powdery white core. Found ubiquitously in modern residential and commercial structures.