any member of a group of common silicate minerals that have similar crystal structures and chemical compositions. They may be colourless, black, and many shades of red and green.
Garnets, favoured by lapidaries since ancient times and used widely as an abrasive, occur in rocks of each of the major classes. In most rocks, however, garnets occur in only minor amounts—i.e., they are accessory minerals. Nevertheless, as a consequence of their distinctive appearances, they are frequently recognized in hand specimens and become part of the name of the rock in which they are contained—e.g., garnet mica schist.
The-structure-of-garnetThe structure of garnet. This schematic diagram of part of the garnet structure shows the …
Dodecahedron-a-common-crystal-form-of-garnetDodecahedron, a common crystal form of garnet.[Credits : Miller Museum of Geology and Mineralogy, Queen’s University at Kingston, Ont., Can.]
Trapezohedron-a-common-crystal-form-of-garnetTrapezohedron, a common crystal form of garnet.[Credits : © Wendell E. Wilson]
Dodecahedron-trapezohedron-combination-a-common-crystal-form-of-garnetDodecahedron-trapezohedron combination, a common crystal form of garnet.[Credits : Miller Museum of Geology and Mineralogy, Queen’s University at Kingston, Ont., Can.]
Photomicrograph-showing-corroded-garnet-surrounded-by-a-corona-of-cordieriteFigure 1: Photomicrograph showing corroded garnet (gray) surrounded by a corona of cordierite …[Credits : Jane Selverstone]
GarnetGarnet[Credits : Harold and Erica Van Pelt]
Link to this article and share the full text with the readers of your Web site or blog-post.
If you think a reference to this article on "garnet" will enhance your Web site,
blog-post, or any other web-content, then feel free to link to this article,
and your readers will gain full access to the full article, even if they do not subscribe to our service.
You may want to use the HTML code fragment provided below.
We welcome your comments. Any revisions or updates suggested for this article will be reviewed by our editorial staff. Contact us here.
Regular users of Britannica may notice that this comments feature is less robust than in the past. This is only temporary, while we make the transition to a dramatically new and richer site. The functionality of the system will be restored soon.