Metal-coated crystals are artificial products made by coating

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

s, such as

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The Atom, atoms are linked in a continuous framework of SiO4 silicon–oxygen Tetrahedral molecular geometry, tetrahedra, with each oxygen being shared between two tet ...

, with metal to give them an iridescent metallic sheen. Crystals treated this way are used as

gemstone A gemstone (also called a fine gem, jewel, precious stone, semiprecious stone, or simply gem) is a piece of mineral crystal which, when cut or polished, is used to make jewellery, jewelry or other adornments. Certain Rock (geology), rocks (such ...

s and for other decorative purposes. Possible coatings include

gold Gold is a chemical element; it has chemical symbol Au (from Latin ) and atomic number 79. In its pure form, it is a brightness, bright, slightly orange-yellow, dense, soft, malleable, and ductile metal. Chemically, gold is a transition metal ...

indium Indium is a chemical element; it has Symbol (chemistry), symbol In and atomic number 49. It is a silvery-white post-transition metal and one of the softest elements. Chemically, indium is similar to gallium and thallium, and its properties are la ...

titanium Titanium is a chemical element; it has symbol Ti and atomic number 22. Found in nature only as an oxide, it can be reduced to produce a lustrous transition metal with a silver color, low density, and high strength, resistant to corrosion in ...

niobium Niobium is a chemical element; it has chemical symbol, symbol Nb (formerly columbium, Cb) and atomic number 41. It is a light grey, crystalline, and Ductility, ductile transition metal. Pure niobium has a Mohs scale of mineral hardness, Mohs h ...

and

copper Copper is a chemical element; it has symbol Cu (from Latin ) and atomic number 29. It is a soft, malleable, and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a pinkish-orang ...

. Other names for crystals treated in this way include aqua aura, angel aura, flame aura, opal aura or rainbow quartz.

Production

Such products are created in a vacuum chamber by vapour deposition. Quartz is heated to 871 °C in

vacuum A vacuum (: vacuums or vacua) is space devoid of matter. The word is derived from the Latin adjective (neuter ) meaning "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressur ...

, and golden wire is heated to even higher temperature, either by resistive heating with direct electrical current, or by magnetron. Gold

sublimation (phase transition) Sublimation is the Phase transition, transition of a substance directly from the solid to the gas state, without passing through the liquid state. The verb form of sublimation is ''sublime'', or less preferably, ''sublimate''. ''Sublimate' ...

occurs, the resulting vapor depositing onto the crystal's surface. When viewed under a gemological microscope in diffused direct transmitted light, aqua aura displays the following properties: *a coppery surface iridescence in tangential illumination *diffused dark outlines of some facet junctions *a patchy blue colour distribution on some facets *white facet junctions, irregular white abrasions and surface pits, where the treatment either did not "take" or had been abraded away. The brilliant color of these products is the result of optical interference effects produced by layers of metal.

In culture

American animated series

Steven Universe ''Steven Universe'' is an American animated television series created by Rebecca Sugar for Cartoon Network. It tells the coming-of-age story of a young boy, Steven Universe (character), Steven Universe (Zach Callison), who lives with the Crys ...

introduced two versions of Rainbow Quartz, a personified fusion of two distinct gem characters: in 2015 with

Pearl A pearl is a hard, glistening object produced within the soft tissue (specifically the mantle (mollusc), mantle) of a living Exoskeleton, shelled mollusk or another animal, such as fossil conulariids. Just like the shell of a mollusk, a pear ...

and Rose Quartz forming the first Rainbow Quartz, and in 2019 with

and

Steven Stephen or Steven is an English first name. It is particularly significant to Christians, as it belonged to Saint Stephen ( ), an early disciple and deacon who, according to the Book of Acts, was stoned to death; he is widely regarded as the firs ...

forming Rainbow Quartz 2.0.

References

External links

Crystals Gemstones {{gemology-stub

Production

In culture

See also

References

External links