from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A gray mineral, chiefly K2Al3(OH)6(SO4)3, used in making alum and fertilizer.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A gray, water-soluble mineral, potassium aluminium sulphate; the natural source of alum, KAl3(SO4)2(OH)6.
from the GNU version of the Collaborative International Dictionary of English
- n. Alum stone.
from The Century Dictionary and Cyclopedia
- n. Same as alum-stone.
Enough potash, however, is obtained in the United States for munition purposes from the burning of seaweed on the Pacific Coast, from the brines in a lake in Southern California and from a rock called alunite in Utah.
Pacific Coast, from the brines in a lake in Southern California and from a rock called alunite in Utah.
For each, there are several kinds of geologic concentrations that represent actual or potential resources; consequently, for each we may expect the depletion history to consist of a series of production-history curves, as availability and cost dictate a steplike descent from high-grade hematite to taconite to iron-rich intrusive bodies, and from bauxite to alunite to high-alumina clays.
It has been found difficult to explain the presence of the alunite except through the agency of surface oxidizing waters acting on hydrogen sulphide coming from below.
One of the interesting features of this occurrence is the abundance of alunite.
At Goldfield, Nevada, native gold is found in surface igneous flows of a dacite type, which have undergone extensive hydrothermal alterations characterized by the development of alunite (a potassium-aluminum sulphate), quartz, and pyrite.
Of other natural mineral sources, alunite is the most important.
In the Goldfield camp (p. 230) the ores are closely associated with alunite in such a manner as to suggest a common origin.
Minor amounts have been extracted in Utah from the mineral alunite (a sulphate of potassium and aluminum), in Wyoming from leucite (a potassium-aluminum silicate), in
Various potassium silicates -- leucite, feldspar, sericite, and glauconite -- and the potassium sulphate, alunite, have received attention and certain of them have been utilized to a small extent, but none of them are normally able to compete on the market.