Joined: 27 Nov 2011
|Posted: Nov 27, 2011 12:51 Post subject: List of synthetics and artificial compounds
|Here is a list of synthetic minerals and artificial compounds:
1)Main synthetic gems:
-synthetic beryl (in many colors) and synthetic emerald (flux or hydrothermal synthesis method)
-synthetic chrysoberyl and color-change synthetic alexandrite (Czochralski pulling method, Floating zone method, flux method, or hydrothermal synthesis method)
-synthetic corundum, in many colors (several existing processes: flux synthesis method, hydrothermal synthesis method, and also several melt processes such as Verneuil flame fusion method, Czochralski pulling method, Kyropoulos method, Bridgman-Stockbarger method, Heat Exchanger method and Floating zone method)
-synthetic diamond (synthetic diamond is made through high-pressure-high-temperature aka HPHT method, or through chemical-vapour-deposition aka CVD method, and synthetic nano-polycrystalline diamond aka NPD is made through an ultra-HPHT sintering process)
-synthetic forsterite (synth. magnesium silicate made through Czochralski pulling method. Let's note that blue synth.forsterite is used as an imitation of tanzanite).
-synthetic lapis lazuli (ceramic type, sintered sodium aluminium silicate with sulfur Na8(AlSiO4)6S2 But let's note that the chemical composition doesn't exactly match lazurite or hauyne)
-synthetic opal (colloidal synthesis sedimentation process, possibly different kind of fabrications)
-synthetic quartz, in many colors (hydrothermal synthesis method)
-synthetic rutile (titanium oxide, made through Verneuil flame fusion method and Floating zone method. Has been used as a diamond imitation)
-synthetic spinel, in many colors (Verneuil flame fusion method, Czochralski pulling method, and flux method)
-synthetic turquoise (ceramic type, sintered copper aluminium hydrous phosphate CuAl6[(OH)2|PO4]4.4H2O Let's note the absence of iron in the chemical composition)
Topaz (hydrothermal method), Zircon (Flux or hydrothermal method) and Tourmaline (hydrothermal method, small crystals, a few millimeters in size) have been synthesized experimentally but these have not been commercialized. At the present time, tanzanite has not yet been synthesized.
Synthetic jadeite has been produced experimentally (high pressure high temperature process) but was not commercialized, and to my knowledge nephrite has not been synthesized.
2)Other synthetic minerals (but not all commercialized):
synthetic alum (and chrome alum), synthetic apatite, synthetic berlinite, synthetic bismuth crystals, synthetic bromellite, synthetic calcite, synthetic cassiterite, synthetic chabazite, synthetic chalcanthite, synthetic chalcedony, synthetic copper crystals, synthetic cuprite, synthetic diopside, synthetic eulytine, synthetic fluorite, synthetic fresnoite, synthetic gahnite, synthetic gold crystals, synthetic greenockite, synthetic gypsum, synthetic halite, synthetic hubnerite, synthetic lopezite, synthetic malachite, synthetic nickel sulfate (retgersite), synthetic periclase, synthetic peridot, synthetic perovskite, synthetic phenakite, synthetic powellite, synthetic proustite, synthetic scheelite, synthetic sellaite, synthetic silver crystals, synthetic sodalite, synthetic sphalerite, synthetic stibiotantalite, synthetic stolzite (aka PWO), synthetic sulphur crystals, synthetic sylvite, synthetic titanite, synthetic villiaumite, synthetic wulfenite, synthetic wurtzite, synthetic zincite, etc...
1)Main artificial compounds:
Besides plastics, resins, glass and ceramics let's mention:
-cubic Zirconia, aka CZ (cubic ZrO2, made through skull crucible melt process. Used as a diamond imitation)
-gadolinium gallium garnet, aka GGG (Gd3Ga5O12, made through Czochralski pulling method, Floating zone method, or flux method. Used as a diamond imitation)
-moissanite (silicon carbide is made through melt process, CVD or PVT method, or flux method. Used as a diamond imitation. Let's note that there's a natural analogue, however it's very rare and mostly microscopic)
-strontium titanate, aka STO or Fabulite (SrTiO3, made through Verneuil flame fusion method or flux method. Used as a diamond imitation)
-yttrium aluminium garnet, aka YAG (Y3Al5O12, made through Czochralski pulling method, Floating zone method, flux method, or sometimes hydrothermal method. Used as a diamond imitation)
2)Other artificial compounds:
Many different artificial crystals are being synthesized (i.e. well over 100), mostly for optical applications (lasers), and it wouldn't be practical to list them all here. Let's still mention a few ones:
barium titanate, bismuth-germanium oxide (aka BGO), lanthanum-gallium silicate (aka LGS or Langasite), lithium fluoride, lithium niobate (aka LNB or Linobate), lithium tantalate (aka LTA or Litanite), potassium hexacyanoferrate (aka Pruskite), silicon, yttrium-gallium garnet (aka YGG), yttrium-iron garnet (aka YIG), yttrium ortho-aluminate (aka YAlO or YAP), Yttrium orthosilicate (aka YSO), Yttrium ortho-vanadate (aka YVO), Yttrium oxide (aka Yttralox), etc...
Here are links with pictures:
Note: when refractive index isn't found on the supplier website, you can also check here: https://refractiveindex.info/
WHICH SYNTHETIC CRYSTALS ACTUALLY SHOW CRYSTALLINE FACETS:
That is a matter of growth process: flux grown and hydrothermal grown synthetics do show crystalline facets, but synthetic crystals grown by melt processes (Verneuil, Czochralski, Floating zone...) occur as single rounded cylindrical masses called 'boules' which do not look anything like a natural crystal.
However, let's note that such 'boule' can be cut into the shape of a natural looking crystal (with engraved striations to imitate natural growth markings), which is then glued into a natural or reconstituted matrix, or rounded to look like alluvial. Sometimes, to make the stone appear more natural, it is quench cracked so to produce natural-looking fractures in the stone (which fractures may also be filled with some ochre-colour dye or resin so the stone looks like naturally included).
John S. White
Joined: 04 Sep 2006
Location: Stewartstown, Pennsylvania, USA
|Posted: Nov 27, 2011 21:55 Post subject: Re: List of synthetics and artificial compounds
|Not sure what the purpose of this is, but I feel that, at best, this is a very partiial list. Many (most?) of the native elements have been synthesized, and what about chalcanthite, zincite, gypsum, plus a multitude of others? If there is an effort to add to this list then I think it would make good sense to try to organize it into groups according to composition, i.e., elements, oxides, silicates, etc.
John S. White