Gemologist strongly suggest only buying loose diamonds accompanied with a reliable certificate.Establish exactly what you want then begin your search. Make sure that you always compare like with like, or you’ll soon be thrown off the scent.
How to Buy Loose Diamonds :
When shopping around at jewelry stores, be sure to ask each dealer for a 10X loupe so that you may properly examine the interior of the jewel. There are microscopes manufactured specifically for observing loose gemstones. Any store that features such a microscope is obviously in tune with the scientific aspects of diamond grading and diamond clarity.
The absolute best way to view clarity of a diamond is with a stereoscopic binocular microscope with dark field illumination. There are such microscopes manufactured specifically for observing diamonds and gemstones. Any store that features such a microscope is obviously in tune with the scientific clarity grading aspect of diamonds and is likely to be quite specific and detailed with all other aspects of diamond grading.
Should one of the loose diamonds you are considering have a clarity grading of, for example, vs1, have the jeweler show you why it is graded vs1. Know the type and location of the inclusions in the diamond. Make sure you see the inclusions yourself under the loupe or, even better, with a microscope. Loose stones are assigned a diamond clarity grade using a microscope with the power of 10X. When observing them with a loupe bring the loupe right up to your eye and then slowly bring the diamond with the tweezers close to the loupe until it comes into focus.
Always look through the tables of loose diamonds to view their inclusions. Pick the stone up with tweezers by putting them table down and firmly grasping them with both sides of the tweezers. After carefully observing the diamond through the table, focus on the side so you can see the girdle. The girdle separates the crown, or top section, of the diamond from the pavilion, or bottom section.
Do not forget to ask the jeweler to allow you to view the diamonds color against a master comparison set. The jeweler will position the diamond against other stones of known color so you may compare. This master set should have already been graded for diamond color by the Gemological Institute of America.
In addition while looking at loose diamonds ask the jeweler to explain the cuts grade to you. If you are looking at a diamond with a round brilliant cut, ask for the following details:
- Maximum diameter
- Minimum diameter
- Table measurement
With these measurements you can determine the table and depth percentage. When judging, be careful of loose diamonds that have a girdle that is too thick
Loose diamonds are most commonly found in following shapes: baguette, emerald, heart, marquise, oval, pear, princess, radiant, round and trillion. The most popular shape has been the round brilliant because people believed it to be the ideal cut that displays the most brilliance and sparkle.
Fancy shapes such as the heart, pear, marquise, oval, and princess diamond cuts are all designed to maximize the carat weight. Usually the rough diamonds will be cut into whichever shape that requires the least amount of sacrifice. Loose marquise and oval shaped stones should have a length exactly twice that of the width. If they are too narrow or too wide, the diamonds will loose light and appear too dark.
Ideally the observation of color should be done under specific fluorescent lighting conditions in a Diamond Lite machine and wearing a 4X optivisor. The GIA Diamond Lite machine houses all the official comparison diamonds on a special tray that fits into the machine. The diamonds are set in order of color within an angled slot so that you may observe the color of these diamonds by looking through the body of the diamonds.
The diamond in question is positioned on the angled slot next to the comparison diamond and in this way a direct comparison can be made with all the comparison diamonds in order to ascertain the correct color of the diamond in question. The diamond in question is shifted from one position to another within the angled slot so that it is between two different stones with each shift. A qualified jeweler or gemologist with this equipment should be able to demonstrate this to you.