A jewelry box you inherited: how to tell what is valuable before you keep, reset or sell

The quick way to sort an inherited jewelry box

Start with the tiny stamps. A karat mark such as 14K or 18K, or a platinum or sterling mark, next to a maker's name or trademark, tells you the piece is likely precious metal and worth a closer look. Stones are harder: a natural diamond, a lab-grown diamond and a good imitation can look the same to the eye, so only testing by a jeweler tells you what you have. Sort by marks first, keep everything together, and have the promising pieces examined before you sell, reset or give anything away.

I am Adam Bitton, owner of Bitton Diamonds, a family-owned jewelry store in Dallas. Helping people understand and sell jewelry they inherited is a regular part of my work, alongside designing engagement rings. The families I meet usually feel two things at once: attachment to the pieces and uncertainty about what they are. This guide is meant to help with the second, so you can make decisions about the first with clear eyes.

Reading the marks inside bands and on clasps

Get a magnifying glass and good light, and look inside ring bands, on the back of pendants, and on the small tag near a necklace or bracelet clasp. The FTC's guide to buying precious metal jewelry explains the most common marks. Pure gold is 24 karat; a piece marked 18K is 18 parts gold and six parts other metal, and 14K is 14 parts gold and 10 parts other metal. The FTC also advises looking for a company's name or registered trademark near the karat mark, since that is the maker standing behind it.

Some marks mean gold over something else. According to the FTC, gold filled, gold overlay and rolled gold plate describe a layer of at least 10 karat gold applied to a base metal, and these should be marked with the karat and the term, such as 14K gold overlay or 12K RGP. Vermeil is gold-plated sterling silver, and gold flashed or gold washed means a very thin plating that wears away. Those pieces can be lovely to wear, but their value is mostly in the design, not the metal.

• 10K, 14K, 18K or 22K, often with a maker's trademark: karat gold
• Numbers such as 850 Plat., or a platinum mark with its purity: platinum
• 925, sterling or sterling silver: 92.5 percent pure silver, per the FTC
• GF, RGP, or the words gold filled or overlay: a gold layer over base metal
• No mark at all: not proof of anything, but a reason to have it tested

Why a stone cannot be judged by looking at it

This is where most guesses go wrong. GIA explains that lab-grown diamonds have nearly the same chemical, optical and physical properties as natural diamonds and can be indistinguishable by eye, while simulants such as glass, cubic zirconia and moissanite are completely unrelated to diamond at the atomic level yet can look convincing. Telling them apart takes instruments: GIA describes advanced spectroscopic methods in its laboratory and desktop screening devices that jewelers use.

The FTC puts it simply in its consumer guide to gemstones: do not assume a stone is a natural diamond because it looks like one. Older pieces add another wrinkle, because a stone may have been treated. The FTC notes that fracture filling is often used to hide cracks in diamonds and that clarity enhancements lessen a stone's value. Kitchen-table tests you find online will not sort any of this out reliably, and some of them can damage a stone or a setting.

What makes one piece worth more than another

Inherited jewelry has value in layers, and it helps to think about them separately. The base layer is the metal: its karat and its weight. The next layer is the stones, which can be worth far more than the metal or almost nothing, depending on what they are, their size and their quality. On top of that, a piece by a recognized maker, or a design that people want to wear today, can be worth more as a finished piece than the sum of its materials.

Condition matters at every layer. A worn shank, a missing stone or a broken clasp changes what a piece is worth and what it would cost to restore. So does wearability: a ring nobody in the family would wear may still have a beautiful center stone that deserves a new setting. When I look at a piece, I explain which of these layers carries its value, because that answer usually tells you what to do with it.

• Metal: the karat and the weight of gold, platinum or silver
• Stones: what they are, how large, their quality and any treatments
• Maker and design: signed pieces and styles that people want today
• Condition: wear, missing stones, repairs needed
• Paperwork: old receipts, appraisals or grading reports that prove what is there

Keep, reset or sell: choosing what happens to each piece

Most families end up doing a little of all three. Some pieces are kept as they are because someone wears them or simply cannot part with them, and those deserve proper insurance, which I cover in my guide on insuring and documenting fine jewelry. Some pieces have a good stone in a dated or damaged setting, and those are candidates for a new design. My store does custom design work that can transform an heirloom, and a grandmother's diamond in a new engagement ring is one of the most meaningful projects I take on.

The rest are usually sold, and that is nothing to feel guilty about. Turning pieces nobody will wear into money for something the family needs is a reasonable choice. If you go that way, read my guide on selling diamond jewelry or a watch for a fair price first, so you know what a fair process looks like before you accept an offer from anyone.

What to do before anyone examines the pieces

A few simple precautions protect both the jewelry and your options. If the estate is still being settled, the jewelry may need to be accounted for before anything is divided or sold; that is a question for an estate attorney, and Marshall Medlin is an estate planning attorney I would point families toward. Otherwise, the rules are about keeping things intact and documented.

• Keep pieces together with any boxes, receipts, appraisals or grading reports
• Do not pry stones out of settings or try to separate parts
• Skip scratch tests, acid kits and harsh cleaners, which can damage metal and stones
• Photograph each piece and make a simple numbered list
• Store everything in one secure place until decisions are made
• Write down what you know of each piece's history, even if it is a guess

Signs a piece deserves a professional look

You do not need to bring in every bead necklace, but some features should move a piece to the top of the pile. A karat or platinum mark with a maker's trademark is the first. A center stone held in its own prongs, rather than glued in, is another, because fine jewelry is built to hold valuable stones securely. A signature or maker's name on the piece, old paperwork from a jeweler, or an original box from a known store all suggest someone paid real money for it.

Weight is a quieter clue. Solid gold and platinum feel heavy for their size, while plated and costume pieces tend to feel light. None of these signs proves value on its own, and their absence does not prove a piece is worthless. They simply help you decide where to start when the box is full and the time is limited.

If the inheritance includes a watch

Watches follow different rules from rings and necklaces. A luxury watch is valued mostly on its brand, model, reference number and condition, and on whether the original box and papers survived. Before you do anything else, find the reference number, which is usually engraved on the case or listed on the papers, and write it down with the brand and model. Do not polish the case or open the back yourself, since both can reduce what a collector will pay.

My store buys luxury watches as well as jewelry. Through the Sell A Watch form on my website, you enter the brand, model, reference number and condition and receive a quote within 24 hours. Even if you plan to keep the watch, knowing what it is worth helps you insure it properly and decide whether it needs service before anyone wears it again.

How an evaluation works when you bring pieces to me

Book an appointment through my website or call the store, and bring everything you are unsure about along with any paperwork. I look at each piece, identify the metal and the stones, and tell you plainly which layer carries the value and what I think the sensible next step is. If a stone is worth building something new around, I will say so; if a piece is worth more to the family than to the market, I will say that too.

If you decide to sell, I explain how I arrive at an offer for each piece, so you understand the number rather than just receiving it. There is no pressure to decide in the room, and you are welcome to take the information home and think. Whether you are in Dallas or elsewhere in the area, the first conversation starts the same way: what is here, and what does it mean to you.

Questions people ask me