(1) The ore zone is a combination of veinlets, lenses, and nests of pyrite and quartz .

(2) Outside we saw large tables covered high with specimens of kyanite in quartz .

(3) Other minerals found here are the red ochre, soap stone, white quartz and molding sand.

(4) These granite dikes are composed almost totally of potassium feldspar and quartz .

(5) There is much chlorite growth, but quartz is only very poorly recrystallized.

(6) The grey colour of quartz is a mineralogical standard showing that the thickness is correct.

(7) My necklaces are made mainly of semiprecious stones, such as agate, quartz , amber, rock crystal and jade.

(8) The intervening area is dominantly a mixture of clay and quartz .

(9) Where pyrite crystals have been lost, it can be seen that quartz did not penetrate pyrite.

(10) These soils have a typical, immature tropical soil mineral assemblage dominated by kaolin, quartz and goethite.

(11) Because they formed within the peat, coal balls generally contain very little detrital clay minerals and quartz .

(12) The white material is quartz and the black is the wall rock from the edge of the vein.

(13) The siltstones are composed of angular quartz and rare feldspar, set in a finer matrix that locally contains some calcite.

(14) All three are dominated by unaltered muscovite, quartz , K-feldspar and albite, with minor epidote.

(15) As a result, quartz is an uncommon gangue mineral within most of the district.

(16) Late chlorite and carbonates overgrew the schistosity defined by phengite, chlorite and quartz .

(17) Adjacent to the gray quartz with acanthite and gold is sugary white quartz with massive galena.

(18) Mylonitic rocks usually have ribbon quartz and rotated albite porphyroclasts.

(19) The sample is strongly foliated and consists of garnet, biotite, quartz , plagioclase and cordierite.

(20) Some topaz forms spectacular crystals and matrix specimens on magnesite or quartz .