Amphibole | mineral | Britannica.com

Amphibole, any of a group of common rock-forming silicate minerals. Amphiboles are found principally in metamorphic and igneous rocks. They occur in many metamorphic rocks, especially those derived from mafic igneous rocks (those containing dark-coloured ferromagnesian minerals) and siliceous

PUBLICATION FORUMBOOK REVIEWS - Elements

ELEMENTS 212 JUNE 2008 PUBLICATION FORUMBOOK REVIEWS AMPHIBOLES: Crystal Chemistry, Occurrence, and Health Issues1 As noted in the preface, volume 9 of the Reviews in Mineralogy series, Amphiboles and Other Hydrous Pyriboles, published 25 years ago, seemed to contain all that was

USGS Report: Dispersion of fibrous amphiboles by glacial ...

used in combination with data from the reports mentioned below, especially the report of Alden (1953). The glacial history of the area was reconstructed to: (1) help identify the source areas of LA found in the lake sediments (Adams et al. 2010), (2) to explain the occurrence of the LA, and (3) to help define the potential distribution of the LA.

Background Information on Asbestos - NCBI Bookshelf

Asbestos is a term applied to several mineral species when they occur in a fibrous form (asbestiform). When the mineral species are asbestiform, they have the physical characteristics associated with asbestos, such as large aspect ratio of fibers, flexibility, separability and weavability of fibers, and chemical and physical durability. However, in addition to those common properties, each ...

Amphibole | Minerals Education Coalition

Amphibole. Amphibolite is a dark, heavy, metamorphic rock composed mostly of the mineral amphibole. Amphibolites have very little to no quartz. "Amphibole" refers not to a single mineral, but to a group of minerals. Most belong to the monoclinic crystal system, but some belong to …

Hornblende Mineral | Uses and Properties

Uses of Hornblende. The mineral hornblende has very few uses. Its primary use might be as a mineral specimen. However, hornblende is the most abundant mineral in a rock known as amphibolite which has a large number of uses. It is crushed and used for highway construction and as railroad ballast.

Occurrence and chemical composition of amphiboles and ...

Amphiboles are found in the corundum-bearing rock, locally in association with extremely Al-poor orthopyroxene (Low-Al OPX). In this paper, petrological and geochemical studies revealed that amphiboles and Low-Al OPX in the studied samples were formed by infiltration of aqueous fluids in the late stage of exhumation of the Horoman Complex.

Asbestos fibre identification vs ... - SpringerLink

May 11, 2014· An attempt to detect the occurrence of electron density at A, Am, and A2 failed in keeping with none or small (<0.01 apfu) cationic excess at M4 for all investigated samples. Preferred orientation for amphiboles was modelled by means of spherical harmonics (nine refinable parameters up to the 8th order).

Amphiboles & Phyllosilicates - tulane.edu

Occurrence- Chlorite is a common mineral in low grade metamorphic rocks, where it occurs in association with minerals like actinolite, epidote, and biotite. It also forms as an alteration product of pyroxenes, amphiboles, biotite, and garnet in igneous as well a metamorphic rocks.

Amphibole - Wikipedia

Amphibole (/ ˈ æ m f ɪ b oʊ l /) is an important group of inosilicate minerals, forming prism or needlelike crystals, composed of double chain SiO 4 tetrahedra, linked at the vertices and generally containing ions of iron and/or magnesium in their structures. Amphiboles can be green, black, colorless, white, yellow, blue, or brown. The International Mineralogical Association currently ...

Libby Amphibole Asbestos - Case Studies

Libby, Montana, a small town nestled in the northwestern corner of the state, is a humble town, a great destination for anglers and hunters. What many people don't know about Libby, is the lurking danger hanging over the heads of the 3,000 or so Libby residents. Located nearby is an old vermiculite mine that has created a health hazard dealing with asbestos.

Amphibole - Chemeketa Community College

Hornblende is the name applied to the dark gray or essentially black-to-greenish black amphiboles that occur in many igneous rocks. The alkali-amphibole group includes three series whose individual members are relatively common in either metamorphic or alkalic igneous rocks. Hornblende uses include: decoration, dimension stone.

Pyroxene Group Minerals | Physical - Optical Properties ...

Augite; Pyroxene is a set of essential rock-forming inosilicate minerals discovered in many igneous and metamorphic rocks.Pyroxenes have the general components is XY(Si,Al)2O6. Although aluminium substitutes extensively for silicon in silicates consisting of feldspars and amphiboles, the substitution occurs only to a confined extent in most pyroxenes.

Amphibolite - Metamorphic Rocks

Amphibolite is a common metamorphic rock. It is made of amphiboles (usually hornblende) and plagioclase. Most samples have a relatively simple composition: hornblende + plagioclase.Garnet (almandine), pyroxene, biotite, titanite, magnetite, epidote, …

Granodiorite - Wikipedia

Granodiorite (/ ˌ ɡ r æ n oʊ ˈ d aɪ ə r aɪ t, -n ə-/) is a phaneritic-textured intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar.According to the QAPF diagram, granodiorite has a greater than 20% quartz by volume, and between 65% to 90% of the feldspar is plagioclase. A greater amount of plagioclase would designate the rock as ...

Occurrence and origin of Cl-rich amphibole and biotite in ...

Abstract. Analyses of Cl-bearing amphiboles and biotites from more than 20 occurrences around the world have been reviewed. The Cl-content of amphibole ranges up to about 6 wt%, while the most Cl-enriched biotite contains about 7 wt% Cl.

DIVERSITY AND OCCURRENCE OF POTASSIUM-DOMINANT AMPHIBOLES …

However, as a result of an evaluation of compositions of Cl-bearing amphibole samples from iron-oxide-rich ore systems and a comparison with data in the reviewed literature, fourteen additional naturally occurring potassium-dominant amphiboles can be justified from selected published chemical data using recommended protocols for normalization.

Asbestos: Geology, Mineralogy, Mining, and Uses - USGS

Asbestos: Geology, Mineralogy, Mining, and Uses by Robert L. Virta1 Open-File Report 02-149 Prepared in cooperation with Kirk-Othmer Encyclopedia of Chemical Technology, Online Edition, Wylie-Interscience, a division of John Wiley & Sons, Inc., New York, NY

ASBESTOS (CHRYSOTILE, AMOSITE, CROCIDOLITE, TREMOLITE ...

Current use of asbestos varies widely. While some countries have imposed strict regulations to limit exposure and others have adopted bans, some have intervened less, and continue to use varying quantities of asbestos ().According to recent estimates by the US Geological Survey, world production of asbestos in 2007 was 2.20 million metric tonnes, slightly increased from 2.18 million metric ton ...

Amphibolite: Metamorphic Rock - Pictures, Definition & More

Uses of Amphibolite. Amphibolite has a variety of uses in the construction industry. It is harder than limestone and heavier than granite. These properties make it desirable for certain uses. Amphibolite is quarried and crushed for use as an aggregate in highway construction and as a …

Reported Historic Asbestos Mines, Historic Asbestos ...

Ross, Malcolm, and Nolan, R.P., 2003, History of asbestos discovery and use and asbestos-related disease in context with the occurrence of asbestos within ophiolite complexes, in Dilek, Yildirim, and Newcomb, Sally, eds., Ophiolite concept and the evolution of geological thought: Geological Society of America Special Paper 373, p. 447-470.

Differences Between Pyroxene and Amphibole | Difference ...

Pyroxene vs Amphibole. Crystals are basically forms of minerals that have the elements, atoms, molecules and ions in a structured pattern. Crystallography is the study of crystals wherein crystallographers use microscopes and other materials to study the different forms of crystals.

University of Minnesota's Mineral Pages: Amphibole

Although most asbestos comes from chrysolite, rather than amphiboles, the widespread past use of asbestos poses some serious health risks. The same fibrous character of the asbestos minerals that allow them to be woven into fabric or used as insulation also allows small fibers to be easily broken off.

Mode of occurrence and geochemistry of amphibole in the ...

The Proterozoic Aravalli-Delhi Fold Belt in western India hosts some of the most important base metal sulfide deposits in the country, among which the Khetri group of deposits, No

Inosilicates (Pyroxenes and Amphiboles) - Tulane University

Occurrence and Distinction of the Pyroxenes. Augite - is commonly found in both plutonic and volcanic igneous rocks, as well as high grade meta-igneous rocks like gneisses and granulites. It is easily distinguished from amphiboles by the nearly 90 o cleavage angles, and is distinguished from Opx by inclined extinction relative to the {110} cleavage, as discussed above.

Amphibole Supergroup: Mineral information, data and ...

The name amphibole (Greek αμφιβολος - amphibolos meaning 'ambiguous') was used by René Just Haüy to include tremolite, actinolite, tourmaline, and hornblende. The group was so named by Haüy in allusion to the protean variety, in composition and appearance, assumed by its minerals. This term has since been applied to the whole group.

The occurrence of Zr-bearing amphiboles and their ...

/ The occurrence of Zr-bearing amphiboles and their relationships with the pyroxenes and biotites in the teschenite and nepheline syenites of a differentiated dolerite boss, Islay, NW Scotland. In: Mineralogical Magazine. 2000 ; Vol. 64. pp. 459-468.

Volume 41 December 2003 Part 6 - rockptx.com

amphiboles occur in diverse geological settings, and (3) the use of chemical modifiers and species names were inconsistent prior to Leake et al. (1997), resulting in a limbo for recognition of potassium-dominant amphibole species. Consequently, several of the potassium-rich amphiboles compiled by Deer et al. (1997), as well as