- Jeweler’s loupe or magnifying glass (10x to 20x magnification recommended)
- Pen and paper
- Jeweler’s watch-opening tool
- 10kt, 12kt, 14kt, 18kt, silver, and platinum acid test kits with stone (optional)
Identifying a watch case or testing it to see if it is 14-karat, or some other gold karat content, requires some simple instructions and basic inexpensive acid testing kits. Basic kits and tools are available online at a variety of auction sites and website stores. Although most antique gold watches and jewelry are stamped with a hallmark number and symbol, not all of them are so identified. So knowing how and where to look for the hallmark symbols and numbers is an important part of identifying 14kt gold watch cases, watches, and jewelry.
Look at the back of the watch case using the jeweler’s loupe or magnifying glass.
Write down any numbers, symbols, and words that you see written on the back of the watch case.
Open the watch itself, from the back, using the watch-opening tool. Be careful not to lose watch parts, and not to scratch the crystal clear face of the watch while doing so. Usually, by rubbing your finger along the outside of the watch case, you will be able to feel a small notch area where the back of the watch is meant to be opened using a jeweler’s watch opening tool. If you do not have or cannot find a jeweler’s watch tool to use, try using a U.S. quarter coin to flip open the back of the watch case for inspection.
Look at the inside watch case parts with the jeweler’s loupe or magnifying glass and write down any symbols, numbers, and words that you see inside of the watch case. Often, if the watch is 14 kt gold or some other gold karat, the weight of the gold watch case will be etched inside of the watch case.
After writing down the hallmarks, symbols, and words inside of the watch case, look at online resources and references to help identify information about whether the watch is 14 karat gold or some other gold karat quantity. If it is stamped “14k,” “14kt,” “14 kt,” or “14 karat,” then chances are it is 14 karat gold. If it is stamped “rolled gold,” “RGP,” or “gold plated,” then it is not gold through and through, but only gold-plated or gold-filled. This does not mean that the watch is worthless, however, for it might hold some type of antique or collectible value.
If the watch is not hallmarked, stamped, or numbered, purchase and use an acid testing kit to find out whether the watch case has any gold in it.
When in doubt, take the watch case to a local reputable jeweler and let them perform the tests on the gold watch case for you. They may also be interested in purchasing the gold watch case from you at a fair price, or be able to tell you some additional information about the watch case that could be helpful.
If your watch case’s acid tests it as 14kt gold or of a lesser gold karat amount, but does not have gold karat hallmarks on it, don’t get too excited, as it could be that the watch case is gold-plated. Before purchasing a gold acid testing kit, try taking the watch to a local jewelry store to have them test it for gold for you. Gold acid testing kits are often also difficult and confusing to read, and there has been some confusion about what colors the acid turns if the item is gold, and which solution to use when testing white gold.