Choose the stone first, because the color is the reason to buy this chain. Sapphire is the safe pick, hard enough to wear every day, and it fills more than half this page. Opal is softer and wants more care. Take 14K gold in the color you already wear. Buy the length printed on the listing, since most come in one length only, and ask us whether the stones were mined or grown.
The stones: sapphire, ruby and opal tennis chains, and rainbow sapphire
Take sapphire for a chain you can forget about. Sapphire and ruby are the same mineral, the red one called ruby and every other color sapphire, and only diamond is harder. More than half these chains are sapphire, in blue, red, pink, green, yellow or a mixed rainbow row. Ruby sits on only a few, and none of them sold in the year.
Opal gives a milky flash that no sapphire has, and the opal rows run wider. Names like fire, galaxy, forest or cotton candy are names, not stones, so read the description for what is set. Most pieces are tennis rows, one stone to a setting. The tennis chains guide explains that build and the pointer sizes.
Natural or lab-grown: are the sapphires and opals real
Ask us before you pay, because most listings never say where a stone came from. The origin line is filled on 14, and on 12 it reads natural, though that line can speak for the diamonds beside the color. Two say lab-grown, the alexandrite among them. A handful more say natural or genuine in the description, though on some that word is about the diamonds or pearls beside the color.
A grown stone is the same crystal as a mined one. The desk will say which one a row is: name the row on the live chat, or text the row's item number to 212-872-9692 from 10 AM ET.
Metal: white, yellow or rose gold for a sapphire chain in 14K
Take 14K, because nearly every chain here is made in it. Most let you choose the gold color on the listing. White gold makes a blue or red stone look cooler and brighter. Yellow warms it. For a pink row, try rose.
Buyers here took white gold about as often as yellow, far more than they do on plain chains. A couple of pieces are 10K and the cross set is sterling silver, so read the metal line. The men's gold chains guide covers what 14K means.
Width and weight: 3, 4 or 5 mm tennis chain and how much it weighs
Take 4 mm for a row that shows at the collar without taking over. Most rows here run 3 to 5 mm wide. The opal chains go wider, 6 to 7 mm on most of them.
Weight follows the width. A 4 mm sapphire row lists about two and a half grams an inch. A 3 mm row lists closer to two. That is the whole piece, gold and stones together. Nearly half the pieces here list between 40 and 60 grams.
Length: 18, 20 or 22 inch tennis chain
Buy the length printed on the listing, because that is the length you get. Most of these chains are made in one length only, and just a few offer a menu. On most, the length falls between 18 and 22 inches. The few buyers here went short, with 18 inches going out most. If you need another length, ask the desk before you order, since no listing promises one.