Glauconitic Sandstone

Physical Properties

Hardness: 2-3 (Mohs scale), Color: Dull green, greenish-gray to white, Luster: Earthy or dull, Crystal Structure: Monoclinic (as a mineral component), Cleavage: Perfect on {001} but rarely visible in grain form, Specific Gravity: 2.4-2.9.

Formation & Geological History

Formed in marine environments through slow sedimentation and chemical alteration of organic matter and minerals on the seafloor. Glauconite is typically found in shallow marine shelf sediments and is an indicator of slow deposition rates.

Uses & Applications

Used primarily as a soil conditioner or fertilizer due to high potassium content (Greensand). Historically used as a pigment in paints (tervertebr).

Geological Facts

Glauconite is often referred to as 'Greensand' and is used as a geological marker to identify prehistoric marine transgression/regression events. It is a slow-release source of potassium and iron for plants.

Field Identification & Locations

Identify in the field by its distinct greenish-gray hue and crumbly, sandy texture. Often associated with fossiliferous beds. Commonly found in coastal plains like New Jersey, USA or the Isle of Wight, UK.

Identified on: 4/14/2026

Mode: Standard