Diamond Proportions.... Important???

Diamonds are cut in loads of different way, the variety is nearly endless! Round brilliant cut is the most common, it attracts and reflects the best light. A stone cutter by the name of Tolkowsky developed the best cutting of a diamond in order to capitalize on the lights full potential. After he analyzed the passage of light through a diamond, he theorized a set of ideal proportions and the number and arrangement of facets. Through continued study it has been determined that Tolkowkys's formulae were correct. The cut bears his name. Its is usually referred to as the Standard brilliant cut, American Ideal, American cut or Ideal cut.
Today, experts believe that any kind of deviation from these measurements give can greatly diminish the appearance of the stone and its dazzling effects.
This is one of the four C's that must be taken into consideration when buying a diamond engagement ring, the cut is a factor that only man can control and so to look for the best possible cut in a diamond is a serious factor to take into consideration when buying.
Stones can be too shallow, too deep, have too big or small a table and many other cut proportions worth studying.
Its a fascinating area to study and worth the effort!

Grading
Grading for cut is based on the degree of deviation from ideal proportions and finish or the polish a diamond exhibits. Two systems commonly used were by GIA and AGS. The Gia grades are divided into four catagories and the AGS system uses ten. Each of the proportions and finish characteristics is graded seperately and a grade established. In each system, the value of the diamond graded is reduced for each step down the scale.