Your next decision will be with regard to the weight or size of the stone. This is largely dependent on the budget you are working to. But it is important to bear in mind that two stones weighing the same can vary widely in price depending on the quality of the stone. Whilst it is generally the case that the larger the diamond, the greater it's worth this is only true when comparing similar stones.

The weight of a diamond is measured in carats. One carat weighs 0.2 grams and a carat is divided in to 100 "points". A stone weighing half a carat would therefore be said to be one weighing fifty points. (0.50 carats or 50 points). Diamond weighing scales are so sensitive that they are usually encased in glass, and the slightest draught could affect their reading.

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