Hand Trades

All internet sellers of jewelry, Hand Trades included, try hard to get good pictures to show you our products. It is almost impossible to get the picture you see to be actual size. Monitor setting, and how the picture is sized in pixels makes this true. Most dealers will tell you the millimeter size of units of their product. If they don’t, you might want to email them for this information to know what you are getting. Knowing you’re getting the right size before you order lets you get what you really want.

As a quick example, I was looking at a pear shaped jasper for a pendant that the dealer stated was 13 mm long. I measured it on my screen at 3 inches, or over 75 mm. A US penny is 20 mm. The jasper was about ¾ the width of the us penny. A quick guide to millimeters would be some examples. Most mechanical pencil lead is .7 millimeters. A standard lead wooden pencil if about 6.5 mm wide, and a 1 carat round diamond is 6.5 mm wide.

Nearly everyone has in their home a ruler with millimeters on one side and inches on the other. A quick look shows that 1 inch is about 25 (actually 25.4) millimeters. Using your calculator divide millimeters by 25.4 to get inches. Example: a dealer told me they had a Pandora type bracelet in 180 mm. 180 mm divided by 25.4 equals 7.08 or a 7 inch bracelet.

Chain & necklace Measurements: 1 mm is the diameter of most pendant chain for smaller size pendants. 3mm would be fairly large. We use a 1.05 box link chain on several of our earring drops, and pendants. Necklaces are measured end to end including all clasps. Drops, and pendants from chain are usually stated as a separate measurement. Using your ruler, measure a chain you own, then for each 1 inch of drop, or rise of chain or pendant add or subtract 2 inches.

Saltwater Akoya cultured pearls are matched to within ½ mm on pearl strands. An inexpensive plastic caliper is a good way to measure items of pearl or round gemstones that you have. To show how important measurement of pearls can be I just checked a major retail site, and a 6 ½ to 7 ½ inch strand of Akoyas was 41% less than a 7 ½ to 8 mm strand for identical quality. The expensive and rare Tahitian, and South Sea pearls are often larger much larger. Freshwater pearls are not normally as round as Akoyas. These pearls are often referred to as potato pearls due to off round shape. Bigger ones are more expensive in Freshwater pearls as in Akoyas. Read our pearl guide for more pearl details.

Drop Earrings: The length of drop in earrings is usually measured from the connecting point to the bottom of drop. Measure a drop you have and compare to sellers measurement, and you know what you are getting in drop length. Many handmade items from dealers can be customized in drop length to what you want.

Gemologist’s Tips:

In natural gemstones in larger sizes (jasper, tigereye etc.), the mm measurement is more helpful than gram or carat weight. They can be thick or thin, not affecting the look, but greatly affecting the weight.

Calipers are best for round measurements. It’s easy to be off ½ mm with a caliper measurement.

Necklaces measure the full length including clasps. A 2 inch chain addition, or subtraction to the length will move the pendant or chain drop by 1 inch as a rule of thumb.

Always compare identical sizes in pearls: Even 5 1/2 to 6 (Akoyas) would be lower in cost than the next match size of 6 to 6 1/2 mm.

Earring drop length is usually either above or below the jaw line.

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