Rock & Mineral Encyclopedia

Search and identify 1,000+ rocks, minerals, crystals, and gemstones — with properties, formation, colors, hardness, and how to tell them apart.

Sesame Jasper

A finely speckled pale jasper trade stone named for its sesame-seed-like flecks, closely related to Kiwi Jasper.

A mafic volcanic rock speckled with pale spherical 'varioles,' typically formed in rapidly chilled basaltic pillow lavas.

A dark jasper trade stone speckled with pale flecks resembling a starry night sky, valued for its cosmic appearance.

A porous sedimentary rock naturally saturated with bitumen, dark, tarry-smelling, and historically mined for paving.