We see many beautiful gem bead jewelry pieces, created by numerous jewelry designers/famous to hobbyist. Most of these people are very creative artists in their design.
But many of them know little, or nothing, about the materials they are working with and this can lead to disasters. I will try to help you know about the gems and materials you are using and their idiosyncrasies.
Let's start with the basics:
They are minerals and rocks that people consider special, beautiful and of value. Actually, there is no specific definition. If there was a definition, it would include: the specialness and beauty of the stone.
This would also include the color, shine, optical effects, shapes, physical effects, hardness, and rarity of the stone. In the past, "Precious Gem" referred only to: Diamonds, Rubies, Sapphires, and Emeralds (plus, Alexandrites and Pearls), But now the term includes most gems.
In this "PC" world, "Semi-Precious Gem" has fallen out of use because it is demeaning. Plus with the introduction of numerous unknown (i.e. Tanzanite) and previously unused gems (i.e. the Colors of Sapphire) the separation no longer applies
It is a naturally occurring inorganic solid constitute of the earth's crust. Most minerals have their own chemical formula, molecule and crystal forms.
Examples are: Diamond, Sapphires, Peridot, Quartz (includes; Agate, Chalcedony, Jasper, and Opal), Garnet, Tourmaline, etc.
What is a "ROCK"?
A rock is a natural aggregate of different or the same minerals. When you look at a rock, you will usually see some of the different components of it's make up.
Examples: Unakite, Ruby in Zoisite, Lapiz Lazuli, Marble, Tiger Iron, Granite, Gneiss, etc.
What is an "IMITATION"?
Anything made to resemble a natural or synthetic gem. They imitate the look, color, and effect of the original, but they do not have the same chemical or physical characteristics.
Examples include: Glass, Austrian Crystal (leaded glass), CZ, Enamel, Plastics, Dyed Howlite and Marble, "Paste", Chinese Glass gems (Strawberry Quartz, Pineapple Quartz, etc.) etc.
They are crystallized man made products whose chemical and physical properties are, for the most part, identical to their natural counterparts.
Examples are: Synthetic Rubies, Sapphires, Alexandrites, CZ, Chatam Emeralds, Hematine, Quartz, etc.
What is a "MAN MADE" gem?
These are gems that do not occur in nature.
Examples: Gold stone (glass & copper).
Or they are "Block materials", which are reconstituted, crushed natural materials that are mixed with a resin and formed into blocks for cutting.
Examples include: Block Azurite/Malachite, Block Coral, Block Black Onyx, Block Turquoise, etc.
As you can see there are several forms of gems and minerals that you need to take into consideration. These are things you need to know when creating with gem beads.