Definition
Picrite is a variety of high-magnesium olivine basalt that is very rich in the mineral olivine
Ignimbrite is a volcanic rock consisting mainly of pumice fragments, formed by the consolidation of material deposited by pyroclastic flows
History
Origin
Hawaii Islands
New Zealand
Discoverer
Unknown
Patrick Marshall
Etymology
From Greek pikros bitter + -ite, 19th century
From Latin ignis fire + imber, imbr- shower of rain, storm cloud + -ite
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Hard Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
Volcanic
Other Categories
Fine Grained Rock, Opaque Rock
Fine Grained Rock, Opaque Rock