Post subject: List of synthetic and artificial compounds
Posted: Sat Feb 21, 2015 12:42 pm
Gold Member
Joined: Sun Jun 28, 2009 9:56 am Posts: 1284
Here is a list of synthetic minerals and artificial compounds:
SYNTHETIC MINERALS:
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):
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...
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).
Last edited by cascaillou on Thu Dec 20, 2018 9:30 am, edited 50 times in total.
Post subject: Re: List of synthetic and artificial compounds
Posted: Sat Feb 21, 2015 12:44 pm
Gold Member
Joined: Sun Jun 28, 2009 9:56 am Posts: 1284
Of course, if anyone knows about other naturally occuring minerals that have been synthesized as crystals (and I mean not just microscopic crystals!), please report.
Last edited by cascaillou on Tue Dec 15, 2015 11:45 pm, edited 1 time in total.
Post subject: Re: List of synthetic and artificial compounds
Posted: Tue Dec 15, 2015 11:15 pm
Gold Member
Joined: Sun Jun 28, 2009 9:56 am Posts: 1284
I don't get your point. Do you mean why bother about making a difference between synthetic and artificial? It's probably best that way because while artificial compounds (which refers to artificial compounds which have no natural counterpart) would usually only vaguely imitate some natural mineral (with usually only very partially matching characteristics), synthetics on the other hand are artificial counterparts of natural minerals, and usually sharing the same properties thus making detection more tricky.
Post subject: Re: List of synthetic and artificial compounds
Posted: Wed Dec 16, 2015 3:11 am
Valued Contributor
Joined: Wed Mar 26, 2014 8:23 am Posts: 254
I'm just working in a project like this (but in German language) Want to describe all "non-natural" stones which are on the market for The Blue Book CIBJO § 4.2. Artificial products 4.2.1. reconstructed stones 4.2.2. composite stones 4.2.3. synthetic stones 4.2.4. artificial stones 4.2.5. imitations
Many thanks for sharing.
As CIBJO did, I would take instead of "mineral" the definition "material". 4. Normative Clauses 4.1. Natural materials 4.2. Artificial products (non-natural materials)
Correct me if I'm wrong, but haven't there been hydrothermal synthetic spinel crystals grown as well? IIRC, they were desirable because they look like rough diamonds, complete with surface trigons (but they were outies instead of innies, or something like that). That said, I'm not quite sure what the purpose of the list is at the moment--it doesn't look like you're going for total completion, but you haven't gone into much detail about each one either. It seems like you could take this a few different ways, all of them interesting.
Post subject: Re: List of synthetic and artificial compounds
Posted: Wed Dec 16, 2015 6:34 am
Gold Member
Joined: Wed Jan 23, 2013 5:29 pm Posts: 1047 Location: Paris
Is "synthetic opal" really a synthetic opal or rather an artificial compound imitating opal ? I am not sure it is the exact counterpart of the natural material in all its properties.
Actually even the Verneuil flame fusion "synthetic spinel" is under discussion (not the same RI, not exactly the same optical properties, not exactly the same chemical composition...as natural spinel).
Post subject: Re: List of synthetic and artificial compounds
Posted: Wed Dec 16, 2015 7:46 am
Valued Contributor
Joined: Wed Mar 26, 2014 8:23 am Posts: 254
Gilson Opals get their hardness because it contains no water. The lack of water in Gilson opal has currently brought about debates and differences of opinion concerning the final classification of Gilson Opal. Here I have my problems too but I declare it as Synthetic Opal.
Kyocera Opal is an artificial stone because of the ingredient epoxy resin?
Post subject: Re: List of synthetic and artificial compounds
Posted: Wed Dec 16, 2015 10:51 am
Valued Contributor
Joined: Wed Mar 26, 2014 8:23 am Posts: 254
Yes, indeed, Wilke is a good book explaining the Crystal Growing Processes and the ingredients. Not included (as far as I know): - Synthetic Beryll Morganite (since 2013 by Chatham) - Neodym-Glasses (Alexite): colour change glass as imitation for Alexandrite and Zultanite / Diaspore - Nanogem, Alpinite, .... and ... just seen - synthetic colour change star corundum (green saphire): http://images.google.de/imgres?imgurl=h ... AQ9QEIJjAB (please scroll down) lab created star corundums http://i00.i.aliimg.com/img/pb/192/218/ ... 92_870.jpg in several colours and colour-changing.
By the way; I just ordered the Wilke. So long I thought about but now Christmas is coming.....
Users browsing this forum: No registered users and 11 guests
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot post attachments in this forum