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Llanite. Llanite is a porphyritic rhyolite with distinctive phenocrysts of blue quartz (a rare quartz color) and perthitic feldspar (light grayish-orangeish). The brown, fine-grained groundmass consists of very small quartz, feldspar, and biotite mica crystals. Llanite comes from a hypabyssal porphyritic rhyolite dike that intrudes Precambrian ...
Kyanite is a typically blue aluminosilicate mineral, found in aluminium -rich metamorphic pegmatites and sedimentary rock. It is the high pressure polymorph of andalusite and sillimanite, and the presence of kyanite in metamorphic rocks generally indicates metamorphism deep in the Earth's crust. Kyanite is also known as disthene or cyanite.
Dumortierite is a fibrous variably colored aluminium boro - silicate mineral, Al 7 BO 3 (SiO 4) 3 O 3. Dumortierite crystallizes in the orthorhombic system typically forming fibrous aggregates of slender prismatic crystals. The crystals are vitreous and vary in color from brown, blue, and green to more rare violet and pink.
Tile frieze with lotus and grapes. Egyptian faience is a sintered-quartz ceramic material from Ancient Egypt. The sintering process "covered [the material] with a true vitreous coating" as the quartz underwent vitrification, creating a bright lustre of various colours "usually in a transparent blue or green isotropic glass".
Azurite was known in the pre-classical ancient world. It was used in ancient Egypt as a pigment, obtained from mines in Sinai. Ancient Mesopotamian writers report the use of a special mortar and pestle for grinding it. It was also used in ancient Greece, for example on the Acropolis in Athens.
Celestine (the IMA -accepted name) [6] or celestite[1][7][a] is a mineral consisting of strontium sulfate (Sr S O 4). The mineral is named for its occasional delicate blue color. Celestine and the carbonate mineral strontianite are the principal sources of the element strontium, commonly used in fireworks and in various metal alloys.
Ametrine, also known as trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Almost all commercially available ametrine is mined in Bolivia. The colour of the zones visible within ametrine are due to differing oxidation states ...
A mixture of other minerals, often including pyrite. Lapis lazuli (UK: / ˌlæpɪs ˈlæz (j) ʊli, ˈlæʒʊ -, - ˌli /; US: / ˈlæz (j) əli, ˈlæʒə -, - ˌli /), or lapis for short, is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color.