Some Fundamental Knowledge about Physical Property of Jewelry Beads

For most DIY crafter, jewelry beads are the most often used materials while their design projects. In fact, some common beads like the resin beads, glass beads, European beads and gemstone beads are not an easy substance. To purchase the fitful ones for DIY projects may be not so hard for the practiced person, but for most primary learners, choose the beads and charms is really a big problem, for which will lead to some problems after using inappropriate ones. In this article, I will make a brief introduction of the beads’ basic physical properties!

1. Refraction index

Definition: Refraction index is namely the ratio of light’s speed in the air against that in the materials. The higher the refractive index of material, the stronger ability will it refract the light. For make judgments more directly, you can follow the methods: make use of a book, each book contain words is ok. Then put the beads upon the word (certainly the beads and charms must be transparent), the more clear of words means the smaller the refractive index. One compare experiment is the different between crystal and transparent corundum, their refraction index are 1.55 and 1.77 respectively. When put the crystal upon the word, the word presents highly clear but the transparent corundum cannot.

2. Transparency

In general, it can be divided into four grades: transparent, translucent, sub-translucent, and non-transparent.

Firstly: transparent; the most famous gemstones like diamonds and crystal are all belongs to this category.

Secondly: translucent, such as the Tourmaline; while place it upon the words, you can only see the roughly outline.

Thirdly: sub-translucent. The most typical example is the jade. It is pervious to light but men’s eyesight can only see a few of its inner.

Forth: opacity. Most beads and charms for example the Malachite and obsidian are members of this system. In addition, the recently popular beads like the clay beads are regularly opaque.

3. Pleochroism

In summary, the pleochroism is namely on one gemstone, sometimes it will present different shades. This special Optical Phenomenon can only appear on the colored gemstones that own one more Refraction index. When lights pass through different position, it will reflect back to multiple directions, then the shades will present different.

4. Dispersion

As we know that the white light (natural light) is compose by red, orange, yellow, green, blue, indigo and violet ones, dispersion is refers to the phenomenon that when natural light was resolved into the original seven lights, for example the rainbow is also the result of the dispersion.

5. Density and specific gravity.

At first you should understand the definition of these two words; density means the mass of per unit volume gemstone (g/cm³); Specific gravity is the ratio of the jewel’s weight in the air and that in 4C water; the two figures can be equal.

6. Hardness

Hardness is, as the name suggests, how hard the gem is. A commonly used is the Mohs scale. In general, from high to low, they are: Adamas (diamond); Corundum (ruby, sapphire); Topaz (blue topaz, palmer stone); Quartz (crystal); Growth stone; Apatite (moonlight stone); Fluorite; Calcite (ice state stone); Gypsum; Talc.

But in the chart, this is a relative hardness, not the absolute exact hardness of gem itself.