How to Grade Sapphires

Grading sapphires is very similar to grading others gems. The common color range for sapphires consists of primarily blues, yet sapphires can come in many hues and variations depending on the geographic location of their origin and the elements found there. Finding just the right sapphire is a matter of personal taste and, with these grading tips, can be a worthwhile task.

Instructions

1    Find the carat weight of the sapphires. This measurement determines the actual size of the gem and establishes the number of "points" contained in the stone. Typically, one carat of weight equals 100 points.

2    Look at the color of the stone. Grading sapphires can be tricky, as the colors can vary as well as personal taste and opinion. Generally assume that the deeper the color of the sapphire, the higher the value of the gem.

3    Examine each sapphire for clarity. Any inclusions that can be readily seen decrease the value of the stone. Finding a stone with little or no imperfections is very rare.

4    Inspect the gem for its cut. Sapphires benefit from a cut that reflects light well and has a clear "window" through the stone. A window is the surface area that is left uncut that allows you to see into the stone.

5    Consider the location of origin for the sapphire. For decades, Burmese and Ceylon sapphires have been highly prized, but Kashmir sapphires are now in great demand for their rarity.

Tips & Warnings

·         Purchase gems and precious stones from reputable dealers and ask for documentation on any stone being considered.

·         Look at the "zoning" of colors in the sapphire. Often, a stone will exhibit bands of color that are not uniform throughout the stone.

·         Avoid treated and synthetic sapphires.

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