Diamond
Diamonds are the hardest of all natural substances. They have been cherished for millennia by royalty as the ultimate symbol of power and wealth. People of ancient India found diamonds on the ground after monsoon storms and thought that they were solidified lightning.

Carat (First in the 4 C's)

The word "Carat" is derived from the Greek word keration, or "seed of the carob". In ancient times, carob seeds were used to counterbalance scales, and as a benchmark weight due to their predictably uniform weight.

A diamond or gemstone's "Carat" designation is a measurement of both the size and weight of the stone. One "Carat" is a unit of mass that is equal to 0.2 grams (200 milligrams) or 3.086 grains.

A carat can also be divided into "points" with one carat being equal to 100 points, and with each point being 2 milligrams in weight. This means, a 1/2 carat diamond would be 50 points, a 3/4 carat diamond is 75 points, and a 2 carat diamond is 200 points.

When a single piece of jewelry has multiple stones, the total mass of all diamonds or gemstones is referred to as "Total Carat Weight" or "TCW"

Diamond Grading History
In the mid 1950's the Gemological Institute of America developed the scale that is used pretty much world-wide today. The scales were broken into two categories: color and clarity, because each is a separate element. One has nothing to do with the other. The clarity of a diamond refers to the number of inclusions (internal marks) and blemishes (external marks) the diamond may have. For the most part, the clarity of a diamond is determined by how visible those marks may be. Clarity is graded on a scale which ranges from Fl (flawless) to I-3 (very obvious and potentially damaging marks). The GIA color scale replaced terms like "river" and "cape" with letter grades from D (a total absence of color) to Z (very deeply colored). The following charts represent the general grading guidelines.

GIA Diamond Grading Chart (Clarity)

GIA Diamond Grading Chart (Color)