Many of the names you meet at markets, in old jewellery boxes and in web shops were invented to make a cheap stone sound like an expensive one. A "Bohemian diamond" is rock crystal, a "Balas ruby" is spinel, a "Madeira topaz" is citrine. Some of these names are centuries old and were once used in good faith, when stones were still sorted by colour; others are plain sales talk. They are still around, above all on inherited jewellery and old valuations.
The rule is simple: a stone is called by the name of its mineral or variety, and a place name is allowed only when the stone really comes from there. "Ceylon sapphire" is fine when the sapphire is from Sri Lanka; "Ceylon diamond" is never fine, because it is zircon. CIBJO, the world federation of the jewellery trade, lays this down in its Blue Books, and in the European Union a name that misleads a buyer is an unfair commercial practice. A goldsmith names the stone on the invoice by its real name; that invoice is what you keep.
The list
The table follows a widely used European gem reference. It is not complete, because new names keep appearing.
| Trade name | What it really is |
|---|---|
| Adelaide ruby | almandine (garnet) |
| African emerald | green fluorite |
| Alaska diamond | rock crystal |
| American jade | green vesuvianite |
| American ruby | pyrope, almandine or rose quartz |
| Arizona ruby | pyrope (garnet) |
| Arizona spinel | red or green garnet |
| Arkansas diamond | rock crystal |
| Balas ruby | pink spinel |
| Blue alexandrite | blue or purple sapphire |
| Blue moonstone | chalcedony |
| Bohemian diamond | rock crystal |
| Bohemian ruby | pyrope or rose quartz |
| Bohemian chrysolite | moldavite |
| Brazilian ruby | pink topaz |
| Brazilian sapphire | blue topaz |
| Brazilian aquamarine | blue-green topaz |
| Californian ruby | hessonite (garnet) |
| Ceylon opal | moonstone |
| Ceylon diamond | colourless zircon |
| German lapis (Swiss lapis) | jasper dyed blue |
| German diamond | rock crystal |
| Gold topaz | citrine or heated amethyst |
| Indian jade | aventurine |
| Cape chrysolite | green prehnite |
| Cape ruby | pyrope (garnet) |
| Kandy spinel | almandine (garnet) |
| King topaz | orange-yellow sapphire (corundum) |
| Copper emerald | dioptase |
| Korea jade | serpentine |
| Lithia amethyst | kunzite |
| Lithia emerald | hiddenite |
| Madeira topaz | citrine or heated amethyst |
| Marmarosch diamond | rock crystal |
| Matura diamond | colourless heated zircon |
| Mexican jade | limestone dyed green |
| Mexican diamond | rock crystal |
| Montana ruby | red garnet |
| Uralian emerald | demantoid (garnet) |
| Oriental amethyst | purple sapphire |
| Oriental topaz | yellow sapphire |
| Palmyra topaz | citrine or heated amethyst |
| Smoky topaz | smoky quartz |
| Saxon chrysolite | green-yellow topaz |
| Saxon diamond | colourless topaz |
| Salamanca topaz | citrine or heated amethyst |
| Serra topaz | citrine or heated amethyst |
| Siam aquamarine | blue zircon |
| Siberian ruby | red tourmaline |
| Siberian chrysolite | demantoid (garnet) |
| Simili diamond | glass |
| Slave diamond | colourless topaz |
| Spanish topaz | citrine or heated amethyst |
| Strass diamond | glass |
| Transvaal jade | green grossular (garnet) |
| Viennese turquoise | clay dyed blue |
How to spot them
A few patterns recur. A place name plus an expensive stone (Arizona ruby, Alaska diamond, Spanish topaz) is nearly always a cheaper stone from that region. "Oriental" in front of a stone usually means sapphire in another colour. Anything called "-topaz" that is golden yellow is generally citrine or heated amethyst. Anything called "-jade" other than jadeite and nephrite is something else: serpentine, aventurine, grossular, dyed limestone. Read more about jade and zircon and cubic zirconia.
What it means for your piece
A wrong name does not make the stone less pretty, only differently priced. Rose quartz is a fine stone, but not a ruby, and an heirloom with "Bohemian garnet" simply holds real pyrope from Bohemia; that name is correct. If you are in doubt about an heirloom or a purchase, a goldsmith or a gemmologist identifies the stone with a few instruments; see the figures on the properties card. For a stone of value, a laboratory report is the certainty.