Coloured stones consist of two groups: precious and semi-precious stones. Under precious stones the following stones are grouped: Sapphire, Ruby, Emerald, Beryl. Semi-precious stones comprise of: Quartz (including Amethyst, Citrine, Rose Quartz, green Amethyst, Agate, smokey Quartz), Topaz (including blue Topaz, yellow Topaz and smokey Topaz, as well as pink Topaz which have been heat treated), Opal, Pearl, Peridot, Iolite, Garnet. etc. The suitability of a gem for jewellery is determined by its hardness. Jewellers use the Moh's Table of Hardness as a guide to determine whether a gem can be used for a specific piece.
Moh’s Table of Hardness | |
10 | Diamond |
9 | Sapphire, Ruby |
8 | Spinel, Topaz |
7.5 | Emerald, Aquamarine |
7 | Garnet, Iolite, Tourmaline, Amethyst, Citrine, Zircon |
6.5 | Agate, Peridot, Tanzanite |
6 | Moonstone, Rainbow moonstone, Opal |
5.5 | Lapis Lazuli, Turquoise |
2 | Glass |
2.5 | Amber |
For an engagement ring, it is recommended to use diamonds, rubies and sapphires as these stones are hard wearing and will be able to withstand general wear and tear that a ring will go through being worn on a daily basis. In our opinion all other stones are to soft and will show signs of wear very quickly if proper care is not taken. Even then these softer stones will show scratches and chips after a time and are not recommended for pieces worn on a daily basis.
Blue or Violet stones
Blue Sapphire, Tanzanite, Aquamarine, blue Topaz, Tourmaline(Indicolite), Iolite, Amethyst, blue Zircon, blue Spinel, Lapis Lazuli, Turquoise
Green stones
Emerald, green Sapphire, Tzavorite, Tourmaline, Jade, Apatite, Diopside, Dioptase, green Agate, Malachite
Red or Pink stones
Ruby, pink Sapphire, Tourmaline(Rubellite), Garnet(Rhodolite, Alamandine, Pyrope), red Spinel, pink Topaz, Kunzite, Morganite, Rose Quartz, Rhodochrosite
Yellow or Orange stones
Yellow Sapphire, Citrine, yellow Topaz, yellow Tourmaline, yellow Beryl(heliodor) Mandarine Garnet, Cornelian, Fire Opal, Amber
Black, Brown or Grey stones
Smokey Topaz, Tourmaline, Onyx, smokey Quartz, Hematite
Birthstones
Wedding Anniversary Stones and Minerals | |
1 | Rose Beryl |
2 | Crystal |
3 | Chrysoprase |
4 | Moonstone |
5 | Carnelian |
6 | Peridot |
7 | Chrysolite |
8 | Opal |
9 | Citrine |
10 | Turquoise |
11 | Garnet |
12 | Amethyst |
13 | Agate |
14 | Ivory |
15 | Topaz |
25 | Silver |
30 | Pearl |
40 | Ruby |
45 | Sapphire |
50 | Gold |
55 | Emerald |
60 | Diamond |