from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A complex crystalline silicate containing aluminum, boron, and other elements, used in electronic instrumentation and, especially in its green, clear, and blue varieties, as a gemstone.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. A complex black or dark coloured borosilicate mineral.
- n. A transparent gemstone cut from it.
from the GNU version of the Collaborative International Dictionary of English
- n. A mineral occurring usually in three-sided or six-sided prisms terminated by rhombohedral or scalenohedral planes. Black tourmaline (schorl) is the most common variety, but there are also other varieties, as the blue (indicolite), red (rubellite), also green, brown, and white. The red and green varieties when transparent are valued as jewels.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a mineral that is a complex borosilicate and hydroxide of aluminum containing iron and magnesium and calcium and lithium and sodium; it is usually black but occurs in transparent colored forms that are used as gemstones
Manufacturers have added static-reducing technology and replaced traditional wire heating coils with ceramic heating elements; many also have added a gemstone called tourmaline to the internal works — all of which, they claim, help today's dryers work faster and cause less damage than older models.
The tourmaline is a most complex substance; almost every stone obtained has a different composition, some varying but slightly, with mere traces of certain constituents which other stones possess in a perceptible degree.
In its occurrence in basic rather than in acid eruptive rocks, axinite differs from the boro-silicate tourmaline, which is usually found in granite.
The Breo Roam sports watch is made from a material known as tourmaline, a naturally occurring mineral widely used as a semi-precious gemstone.
From time to time we have reports of coal, but the coal is never of a quality which can be burned, consisting of minerals such as tourmaline and iron ore.
Boric acid is also a constituent of certain silicates, such as tourmaline, axinite, and datholite.
Seaward, glimpsed through a fringe of hundred-foot coconut palms, was the ocean; beyond the reef a dark blue that grew indigo blue to the horizon, within the reef all the silken gamut of jade and emerald and tourmaline.
Coral patches uprose everywhere from the turquoise depths, running the gamut of green from deepest jade to palest tourmaline, over which the sea filtered changing shades, creamed lazily, or burst into white fountains of sun-flashed spray.
If I had to design using only three materials , they would be 24-karat gold, aquamarine and tourmaline in their crystal state.
She makes 50 pieces a year using semiprecious stones such as aquamarines, hessonites, chrysoprase and pink tourmaline, and ranging from £800 to £50,000.