Diamonds are weighed on a scale of metric carats, abbreviated “ct.”  It is equal to approximately 1/5 of a gram.  A carat is broken down into 100 points, just like a dollar is broken down into 100 pennies.  When you see a diamond weight of 1.45 ct., it means one carat and 45 points.

The larger a diamond is, the more rare it is.  Diamonds are bought and sold on a pricing concept know as “per carat.”  As diamonds get larger, the price per carat increases due to the rarity factor – a diamond that weighs 2 ct. will be worth more than twice as much as a 1 ct. diamond.