olivine occurs in certain of the Rainier lavas, in stout prisms somewhat rounded and often with reddened borders.
Their essential constituents are olivine and purplish augite.
Each, with numerous illustrations, handsomely bound, olivine edges.
Below this is a more compact basalt, with crystals of olivine.
Chrysolite (peridot, or olivine) was regarded in Shakespeare's time and earlier as of exceptional rarity.
olivine is often present; and when abundant the rock is called "olivine-basalt."
Section of olivine crystal from the lava of 1631—imperfectly formed.
Some of these are composed of trachyte, others of compact blue basalt with olivine.
The contacts of the olivine rocks with gneiss usually produce rich deposits.
In olivine the black enclosures are not thin laminae, but branching growths resembling pieces of moss.
An olive-green to brownish-green orthorhombic mineral. Olivine is a common mineral in the igneous rocks, such as basalt and gabbro, that make up most of the Earth's crust beneath the oceans. Chemical formula: (Mg,Fe)2SiO4. ◇ Olivine in which the mafic component consists entirely of magnesium is called forsterite. Chemical formula: Mg2SiO4. ◇ Olivine in which the mafic component consists entirely of iron is called fayalite. Chemical formula: Fe2SiO4.