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Any of various dark, granite-textured, crystalline rocks rich in plagioclase feldspar and having little quartz.

[French, from Greek diorizein, to distinguish : dia-, apart, between; see dia- + horizein, to divide, limit; see horizon.]

di′o·rit′ic (-rĭt′ĭk) adj.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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* The 2019 exploration program is focused on the expansion and delineation of the gold mineralized zones discovered by the Company as well as Regional Exploration of other areas of the Project in the search for new mineralization and potential new discoveries.Results have been received from the first four holes drilled These holes were designed to ascertain contact angles0x20 and thicknesses of the fresh granites and the dioritic intrusive at Adit A.
The inclusions are dioritic type with distinctive boundary with its host rock and chilled border, which indicates the inclusions are not the residual after partial melting, but the product of magma crystallization.
Dioritic to granitic plutons intruded both the low- and high-grade metamorphic units in both the Creignish Hills and North Mountain areas (Fig.
Several granitic, granodioritic, tonalitic, dioritic and syenitic intrusions close to the quartz veins and minor gold field soils were observed (Figures 12 and 13).
The deposit (37.26 [+ or -] 0.26 Ma) crops out on the southern flank of an E-W-trending range of andesite-dacite volcanic hills where a dioritic pluton intrudes the volcanic cover.
(2009): Generation of tonalitic and dioritic magmas by coupled partial melting of gabbroic and metasedimentary rocks within the deep crust of the Famantinian Magmatic Arc, Argentina.
On completion of early stage exploration there has been encouraging results of gold geochemical and geological, including anomalous gold (BLEG sampling) from stream sediment sampling draining an area of dioritic intrusives.
This local name was given to unusual textured magmatic rocks of largely dioritic and granodioritic composition occurred in area of the Marktredwitz.
Although the mass is considered an entity, it is composed of different materials, ranging from dioritic to monzonitic quartz.
In many ancient arc systems, uplift and erosion have removed much of the volcanic arc, so that the crystallized products of the magma chambers are exposed as large plutonic bodies, typically of granitic to dioritic composition.
Underlain by a Cretaceous dioritic batholith, the property hosts spectacular intrusive hosted copper-gold mineralization in subhorizontal fractures and veins over an area of at least four square miles.
There, four roughly east-west-trending, nearly vertical calcite-galena veins cut Grenville-age granitic and dioritic gneiss; these are the Nash (Coal Hill), Jepson (Pardee, Victoria), Ross and Robinson (Indian River) veins.