Gemstones have always interested human beings from time in memorial. In the past, they were relegated to the rich and the elites in the society. They were featured in their cutlery, household assets and jewelry among other valuables. They have been passing over the years in various family lineages. Today, they still attract the same attention and are pricey. We are all mesmerized by their unique colors and shapes. They feature distinct mineralogy characteristics. They can fall upon various categories depending on color, cut, clarity and rarity upon other determinant factors.
What Characterizes Gems?
The stones can be categorized depending on several factors. However, typically they are grouped based on these factors;
A gemstone can combine one pure element or it can be a product of a mixture of several mineral compounds. Most gems contain both oxides and silicates which give them a characteristic color.
The structure of the crystal
Precious stones can be either single crystal, a collection of massive microscopic crystals such as diamond or an amorphous compound. The crystallized stones can take many forms such as hexagonal, cubic and tetragonal among other sophisticated shapes. These kind of stones require careful cutting to ensure that the shape of the crystals is maintained.
The optical characteristics of many gemstones are derived from their crystal structure and chemical composition. Color is one of the main feature that define gems. Most of them exude stunning hues when light shines upon them. Some will even portray a mixture of colors making them very adorable. Precious stones are also classified depending on their refractive measurements. The refractive capability will vary among various minerals. Clarity is a common term when classifying gems. Some minerals have unique inclusions which can be crystals of other elements, gas or liquid cavities. Such inclusions help in the identification of the stones.
This is defined as the ratio of a density of a gemstone relative to that of water. Some minerals such as amber floats effortlessly on salty water. Others such as diamond will sink regardless of the weight of the crystal.
Not every gem is resistance to breakage. Some such as nephrite are a bit soft whereas diamond is the toughest of them all. All these characteristics among others such as the availability of the mineral helps in placing the gemstones either as precious or semi precious. The hardness of a crystal can be measured by Mohs hardness scale from 1- softest to 10-hardest.
Assessment of Quality of Gems
Four factors are considered while determining the quality of gems. Color is a cruciform aspect when evaluating a colored mineral. There are three qualities of color rarely hue, saturation and tone. Hue is the position of the mineral on the color wheel, it can be red, black, orange, blue and such like. However, there will be variations of a single hue position such a darker and a lighter green and so forth.
Another cruel consideration is clarity. This is gauged by …