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The OED defines pyrope (from Greek Πυρωπός, lit. "fire-eyed")" as: "In early use applied vaguely to a red or fiery gem, as ruby or carbuncle; (mineralogy) the Bohemian garnet or fire-garnet"; and carbuncle or carbuncle-stone (from Latin "carbunculus", "small glowing ember") as: "A name variously applied to precious stones of a red or ...
In contrast, common opal does not display an iridescence, but often exhibits a hazy sheen of light from within the stone – the phenomenon that gemologists strictly term as opalescence. [5] This milky sheen displayed by opal is a form of adularescence .
Luminescence occurs in some minerals when they are exposed to low-powered sources of ultraviolet or infrared electromagnetic radiation (for example, portable UV lamps), at atmospheric pressure and atmospheric temperatures.
A polished almandine stone . Carbuncle (/ ˈ k ɑːr b ʌ ŋ k əl /) is another name for a deep red almandine gemstone that has been cut with a smooth, convex face in a method called cabochon. [1] Traditionally, the term referred to any red gemstone, most often a red garnet. [2] Carbuncles and their chimeras have spanned three millennia.
Asterism on the surface of a blue star sapphire. A purple-pink star sapphire displaying asterism in a platinum ring.. An asterism (from Ancient Greek ἀστήρ (astḗr) 'star' and -ism) is a star-shaped concentration of light reflected or refracted from a gemstone.
The concept of using luminescence dating in archaeological contexts was first suggested in 1953 by Farrington Daniels, Charles A. Boyd, and Donald F. Saunders, who thought the thermoluminescence response of pottery shards could date the last incidence of heating. [15]
Chlorophane, also sometimes known as pyroemerald, cobra stone, and pyrosmaragd, is a rare variety of the mineral fluorite with the unusual combined properties of thermoluminescence, thermophosphoresence, triboluminescence, and fluorescence: it will emit light in the visible spectrum when exposed to ultraviolet light, when heated, and when ...
This is a list of sources of light, the visible part of the electromagnetic spectrum.Light sources produce photons from another energy source, such as heat, chemical reactions, or conversion of mass or a different frequency of electromagnetic energy, and include light bulbs and stars like the Sun. Reflectors (such as the moon, cat's eyes, and mirrors) do not actually produce the light that ...