A loupe is a specialized magnifying glass used for inspecting gems and jewelry. Good ones have 3 lenses in them and magnify at least 10x. To use a loupe, hold it about 1 inch from your eye resting the hand holding the loupe on your cheek. Hold the diamond about 1 inch in front that with your other hand and rest that hand on the first hand holding the loupe. To focus, move the diamond closer or further from the loupe. Keep both eyes open to reduce eyestrain. Once you are comfortable using the loupe, here's what to look for. Read our Diamond Anatomy
page for more details.
Facet...any of the flat “sides” of the diamond.
Table...On a brilliant cut stone, it’s the top octagonal facet.
Girdle...The ring at the widest part of the diamond.
Culet...The bottom point on a brilliant cut stone.
Pavilion...The portion of the stone below the girdle.
Crown...The portion of the stone above the girdle.
Fire...The quality of the diamond that breaks reflected light into a colorful array.
Brilliance...The quality of the diamond that reflects light without changing it (sometimes called sparkle).
Fluorescence...The characteristic of some diamonds to fluoresce certain colors under sun light or a strong UV light.
Natural...Usually found on the girdle. It is a small section that was on the side of the raw diamond. It appears as a slightly rough flat spot on the girdle.
Feather...A jeweler’s way of saying “crack”. It often appears as a white feather shape within the diamond.