Quartz

one of the most common rock-forming minerals, SiO₂, which is found in many different kinds of rock. It also forms some semi-precious stones, e.g. amethyst and agate.

Taken from Dictionary of Science

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Quartz is the second most abundant mineral in the Earth's continental crust, after feldspar. It is made up of a continuous framework of SiO₄ silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall formula SiO₂.

There are many different varieties of quartz, several of which are semi-precious gemstones. Especially in Europe and the Middle East, varieties of quartz have been since antiquity the most commonly used minerals in the making of jewelry and hardstone carvings.

Taken from Wikipedia

Ultrabasic Rock

an IGNEOUS ROCK that contains many silicate minerals of iron and magnesium such as AMPHIBOLES and PYROXENES, and with SILICA occurring as quartz.

Taken from Dictionary of Science

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An igneous rock with a very low silica content and rich in minerals such as hypersthene, augite and olivine. These rocks are also known as ultramafic rocks.

Taken from Geology.com

Jasper

an impure variety of minutely crystalline quartz (SiO2). It is usually red, brown or yellow, and some varieties are banded, e.g. Egyptian or ribbon jasper.

Taken from Dictionary of Science

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Jasper, a form of chalcedony , is an opaque, impure variety of silica, usually red, yellow, brown or green in color. Blue is rare. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone. It can be highly polished and is used for vases, seals, and at one time for snuff boxes. When the colors are in stripes or bands, it is called striped or banded jasper. Jaspilite is a banded iron formation rock that often has distinctive bands of jasper. Jasper is basically chert which owes its red color to iron(III) inclusions. The specific gravity of jasper is typically 2.5 to 2.9.

Taken from Wikipedia