Actual Diamond Sizes on Hand of a 1.00 Carat Diamond
Try to use the 6.5 mm mean diameter for a 1.00 carat stone by measuring the size of your own finger to get an appreciation of what a diamond of this size will look like on your finger. The ring shown in the picture is a US size 6; this is the same as an L 1/2 size in countries like Australia and Britain, and is an average ring size. The ratio of your ring finger's length and its width can play an important role in the final appearance of a diamond on your hand.
The apparent size of the diamond depends heavily on what it is shown against - her hand - a small hand will make the diamond appear proportionately larger, with the reverse applying as well.