A carat refers to the weight of a diamond and a 1 carat loose diamond would actually weight .2 grams Generally the bigger the diamond the more carats or fractions of a carat it is the more it weighs.
A gram of diamond would be a massive 5 carats. Very large in diamond terms although the actual diamond is small A carat is further divided into Points, and there are 100 Points to a carat. So 1 point is .002 of a gram. Very small indeed.
Some jewelers will tell you the a diamond is more valuable because it is bigger and therefore more rare. Be warned, it is not necessarily the case that a diamond is worth more because it is larger. Yes the larger stones are more rare than smaller ones and generally speaking bigger stones will cost more but carat weight is by far not the only criteria to judge a diamond’s worth.
A good quality 1 carat diamond may be worth more in fact than a poor quality 2 carat diamond!
Every diamond should have a certificate from a reputable independent laboratory to indicate the qualities of the diamond and so it’s value.
In diamonds of comparable quality a 2 carat diamond would sell for about 3-4 times the value of a one carat diamond. And the price would increase exponentially which is why a 30 carat diamond can command hundreds of thousands of dollars as against two or three thousand perhaps for a one carat stone.
When choosing a diamond for someone style and finger size is important. A smaller stone can look quite large on a very slim finger while a thicker finger would probably need a bigger stone.
Bigger stones also tend to get knocked around. Don’t believe that a diamond is invulnerable. It is not. A diamond can be damaged, particularly the edges if it is not set well or is roughly treated.
Check out diamonds (with a certificate) within your budget and try to get the best possible at the top range of your budget. A good setting helps too. Platinum is an excellent metal to set an engagement ring in. It is sturdy, strong and less likely to wear away than gold being a harder metal.
The importance of having a certificate as described above for a diamond is vital. Most diamonds that are sold without a certificate are over graded by at least one grade in the color and clarity grades and this can make a tremendous difference in the value. It can mean about a thousand dollar difference in some cases with a 1 carat loose diamond so do ensure you know what you are buying. A certificate from a respected, independent laboratory will give an accurate, unbiased assessment to help you get the best value for your dollar.
So keep the above in mind when you are buying a 1 carat loose diamond and you will likely get a diamond with which she will be well pleased!