Subject: Buying Gems, Pearls, Gold and Jewelry
From time to time I update the essays found in my travel book (https://www.amazon.com/dp/B00V...)

I though the following might be helpful to some here.

Jeff

Jewelry is found in every human society. It is decorative and some think it is a solid investment. I can’t argue with the first, but the latter is less certain. The more types of elements which are included in a piece of jewelry, the more difficult it is to evaluate the value. This makes it more challenging to determine the intrinsic value of, say, a Mexican silver necklace filled with cut stones.

It is generally constructed with materials considered rare and valuable – gems such as diamond, emeralds, sapphires, rubies, and pearls, as well as metals such as gold, silver and platinum. As an example, as of 2026, while the price of gold and silver have dramatically increased over the past few years, diamond prices have dropped by over 40%. People are frequently disappointed with the results when they resell their jewels.

Notice that none of the below dwells on the piece of jewelry, but rather on its components. Other than it is artistic appearance, these are what you are paying for (otherwise, plastic jewelry should sell for as much as gold jewelry). Do not show the seller that you have fallen in love with the ring, rather have him prove the ring is worth the money he is demanding.

GOLD & SILVER
Gold is the easiest material to understand pricing when purchased in Asian markets such as in the Dubai Gold Souk or Bangkok’s Chinatown gold exchanges. Gold is quoted as 24 karat at a market price (sometimes government mandated) prorated by the percentage of alloy, plus the workmanship to create the item (say a bangle or chain necklace) plus a government tax (if required), plus a minimal vendor profit.

The price of gold is subject to external forces influenced by macroeconomic monetary pressures. In those environments, items made from pure (24k) is the most widely accepted, but bangles are frequently made from 22k (91.67%) gold because 24k is so soft they would quickly deform. European gold items are frequently 18k (75%) gold, US gold items are frequently 14k (58%) gold and gold from the UK and its former colonies, frequently 10k (42%) gold.

While in the US, gold is quoted in troy ounces, in most of the rest of the world it is quoted per gram (and there are 31 grams per ounce). To further complicate things, in other parts of the world, foreign weights such as teal, baht and grain as well as foreign currencies may be involved in the calculation.

You can find the “spot” price of gold or silver (in grams, ounces or “whatever”) by using Google or your favorite internet search engine. Using a small Excel spreadsheet with a column for each common purity and rows for each of the common weights can make life easier as the value can easily be found by multiplying the weight of an item by the content of the appropriate box.

While pure or high-percentage silver is used for jewelry in some parts of Mexico and South America, Sterling silver (92.5%, usually marked “925”) is far stronger and more durable and is more frequently used. The “filler” 7.5% of the alloy is usually copper (which can discolor skin) or nickel (which can cause allergic reactions for some), so better pieces are frequently plated with rhodium to prevent these issues. Unmarked silver, especially “folk” pieces, are frequently made from melted coinage (called “coin silver) and is usually 90% pure. In any case, to find the intrinsic value of a piece of silver jewelry, like with gold, multiply its weight times its purity and then multiply that by the “spot price” for the day.

Why bother with the math? Easy – this lets you accurately calculate the “value” of the item. Any price above this number is to pay for workmanship and profit. As the price of gold (or silver) is a “hard stop”, your bargaining technique should be to discuss, and try to reduce, the workmanship/profit number. The salesman pretty much has to agree to your determination of the “value” of the material used to make the piece and, when that is subtracted from the price, has a difficult time explaining his apparent 400% markup (and allows you to bargain up from his cost, rather than be impressed by his willingness to discount)..

Looking at jewelry from this perspective helps avoid becoming “emotionally involved” and paying too much – always be willing to walk away from the shop if you cannot reach a mutually agreeable price (you might be surprised when the salesman calls you back and agrees to your price ).

Gem stones are supposed to enhance the light striking them but, all to often, specific lighting is used to enhance gems in a shop environment. “point sources” (like LED’s) without a yellow spectral component are used to display diamonds, but emeralds look better when light with lots of yellow re used. Take gems outside into natural sunlight to see what they really will look like when worn.

DIAMONDS
Wholesale gem prices are influenced by supply and demand as well as competitive options. Cartels such as DeBeers try to restrict the supply (in their case, in diamonds), while the availability of chemically identical, high quality, lab-grown gems at far lower prices than naturally found ones tends to provide a significant downward pressure on prices.

Also significantly affecting gem prices is the level on the distribution chain that the dealer is located on. For example, diamonds purchased directly from wholesale cutters in such places as Antwerp, Ramat Gan, Amsterdam or New York City have the potential of being far lower in cost than at a retail jeweler (but as a “layperson” gaining access at the wholesale level may not be easy). In the case of diamonds, reseller pricing is frequently based on a discount t from the “Rappaport Report” which documents current prices for excellent cut stones on a matrix of size, color and clarity (separate reports for round and for pear-shape). Usually, any shape will sell for a 15% discount from a round stone and an extraordinarily cut round stone will frequently sell at a premium. The reason for this is that most stones are cut to maximize their weight (a major determinate in the stone’s price), but cutting the stone to optional proportions will frequently cause more scrap and a lighter stone from a given piece of material.

Diamond merchants and engagement ring pushers make much of the “4-C’s” of Carat (size), Color (with “D” white being the most desirable), Clarity (with Internal Flawless being boss) and Cut (not shape as many might think, but rather the symmetry and proportions which cause optimal sparkling and scintillation). Buying diamonds from a wholesaler is akin to choosing a package of chopped beef. You get a larger package for your money if it contains a higher proportion of fat, but both packages are worth what you pay. Some people like to maximize the size for their bucks. Others want everything to be perfection and take a hit on the size. In a world where perfection is budget-busting, my personal preference is decent clarity (say, VSish – not visible without a loupe), decent color (say “G” – white enough to be indistinguishable to the naked eye), but I don’t compromise on the cut – with the logic that I bought the bloody thing to sparkle, so it had better behave better than the bottom of a Coke bottle.

Any “enhancement” to the stone should be disclosed to the purchaser, and reduce the price. While some fancy colors are naturally found and sought after (canary yellow, high cognacs, pink and blue, for example), many colored stones are created by irradiating poor colored stones. This should be disclosed), as well as undesirable colors which have been “branded” to make them saleable (such as chocolate and champagne colors – which previously were only salable as the tips of drill bits). These later two categories should sell at a substantial discount compared to white stones of equivalent cut, size and clarity.

There are, of course, diamond simulants of all sorts. These are not diamonds, but since they are frequently not detectable by the non-expert, if purchasing from any jeweler who is not a sibling, it is important to have an independent gemology lab certify the stone (costs range, depending on country between $15-$40).

COLORED STONES
Colored stones, such as sapphire, ruby. Tanzanite and semi-precious stones are frequently far lower priced at the Columbo, Sri Lanka “World Trade Center” jewelry exchange, at one of the wholesale markets on Sulom Road in Bangkok, Thailand or in Jaipur India. In all three cases, it is extremely important to walk into the shop alone (as any guide or driver will demand a significant commission) and to negotiate vigorously to get the proper price. Other colored stones, such as emeralds, aquamarines as well as semi-precious stones are available in Brazil and Columbia.

There are various shapes closely associated with some gems, due to optics, crystalline structure or custom. Diamond cuts are essentially designed to create a matrix of mirrors and prisms designed to both reflect and refract received light and direct it back out the top of the stone. The most effective shape for this process is a facetted round stone of specific proportions. Other shapes are frequently created to maximize the size of the finished stone, while removing flaws, in order to maximize price rather than maximizing the optics.

Emeralds are more frequently cut in a cube shape and sapphires and rubies as either facetted ovals or smooth cabochons.

"ENHANCING" GEMS
(should be disclosed by honest dealers)

Emeralds naturally have internal fractures (“jardin”). Oiling fills these tiny fissures to improve clarity and appearance. This is a standard procedure and expected for most emeralds - Untreated emeralds are rare and command a premium

How it’s done:
The stone is warmed
A filler (traditionally cedarwood oil) is drawn into surface‑reaching fractures
Modern fillers may include resins or polymers
What you should know:
Oil can dry out or leach over decades, especially with heat or ultrasonic cleaning
Labs grade treatment levels: None / Minor / Moderate / Significant
Buying tip: Minor oil is ideal. Significant oil lowers value and durability.

Heat‑Treating Sapphires and Rubies - Very common and widely accepted. Heat‑treated sapphires are stable and durable - Untreated sapphires with fine color are significantly more valuable

What it is:
Heating sapphire at high temperatures to improve color and clarity.
How it’s done:
Temperatures of 1,600–1,900°C
Can dissolve rutile silk, intensify blue, or lighten overly dark stones
Sometimes combined with diffusion, but that is a different treatment and must be disclosed
What you should know:
Labs report: Unheated vs Heated
Buying tip: If a seller claims “unheated,” always ask for a lab report (GIA, AGL, GRS, SSEF).

Irradiating Diamonds
What it is:
Used to shift the color of a diamond from an undesirable one to a more desirable one. Exposure to controlled radiation to change or intensify color—often producing green, blue, yellow, or black diamonds.
How it’s done:
Electron bombardment or neutron irradiation
Often followed by annealing (heating) to stabilize or shift color
What you should know:
Produces permanent, stable color
Safe to wear; stones are not radioactive
Must be disclosed
Irradiated diamonds are far less expensive than natural fancy‑color diamonds
Buying tip:
If the price seems too good for a vivid fancy color, it’s almost certainly treated.

Significant (order of magnitude) savings can be had by buying lab-grown gems, such as diamond, emerald, ruby and sapphire and having a lapidary cut your desired shape. Another strategy to save money is to buy finished jewelry at estate auctions (requires knowledge of assessing its value).

OPALS
Opals are available in Australia. For the best prices, buy from cutters, not resellers — especially for boulder and crystal opal, either at their location in Australia or over the internet or by auction. Compare per‑carat pricing across at least 3 sellers; opal pricing is highly variable. Check for treatments (doublets, triplets, resin fills). Photograph under multiple lights (sunlight, LED, diffuse) to verify color play

Direct access to opal miners and cutters:
Lightning Ridge (NSW) is best for: black opal, crystal opal, rough parcels.
Coober Pedy (SA) is best for: white opal, large quantities, tourist‑friendly shops.
Winton / Koroit / Quilpie (QLD) is best for: boulder opal, especially large or unusual matrix patterns.

Key Cautions When Buying Opals

1. Beware of “assembled” opals (doublets & triplets) sold as solid opals
These are layered stones:
Doublet: thin slice of opal + backing
Triplet: thin slice + backing + clear cap (usually quartz or plastic)
Risks:
Much cheaper than solid opal
Can delaminate with water or heat
Often misrepresented to tourists
How to spot:
Sharp, flat edges
Perfectly uniform color
Black backing
Dome that looks “too glassy” (triplet cap)

2. Avoid heavily treated or resin‑filled opals
Some low‑grade opals are:
Resin‑impregnated
Smoke‑treated
Sugar‑treated
Dyed
These treatments can dramatically alter appearance but reduce value and stability.
Red flags:
Color looks “too even”
Plastic‑like shine
Very low price for vivid color
Seller avoids answering treatment questions

3. Watch for crazing (cracking) — especially in Ethiopian opal
Hydrophane Ethiopian opal absorbs water and can:
Change color
Become cloudy
Develop cracks over time
How to check:
Look for tiny internal cracks under magnification
Ask if the stone has been water‑tested
Avoid stones that look “milky” or have spiderweb fractures

4. Don’t buy opals that look great only under strong LED lights
Opal sellers sometimes use:
High‑intensity LEDs
Narrow‑beam flashlights
“Jeweler’s spotlighting”
These exaggerate play‑of‑color.
Test the stone under:
Diffuse daylight
Shade
Indoor ambient light
A good opal should look attractive in all lighting.

5. Know the difference between Australian and Ethiopian opal
Australian opal:
Stable
Non‑hydrophane
Higher price
Long‑term durability
Ethiopian opal:
Hydrophane (absorbs water)
More affordable
Can change appearance
Needs careful storage
If a seller won’t disclose origin, be cautious.

6. Be careful with boulder opal weight
Boulder opal includes natural ironstone backing.
Some sellers price by total weight, not opal weight.
Tip:
Price should reflect face‑up opal quality, not the heavy backing.

7. Avoid stones with sand pits, voids, or weak seams
These can:
Break during setting
Trap dirt
Reduce long‑term durability
Inspect edges and the back carefully.

8. Don’t buy opals that feel too light
This can indicate:
Plastic
Resin
Synthetic opal (lab‑grown)
Imitation opal (opalite, “slocum stone”)
Real opal has a solid, stone‑like heft.

9. Ask about stability and return policies
A reputable seller will:
Disclose treatments
Explain origin
Offer returns
Provide documentation
If they resist, walk away.

PEARLS
Pearls are widely available in the Pacific area. Price Drivers: Larger, perfectly round, and deeper colored pearls, with no surface imperfections and high luster are always more expensive.

The industry is heavily focused on pearl farming, which allows for consistent quality and color. China is the world's largest producer of cultured pearls, dominating the market with approximately 95% of all freshwater pearls. Japan, the top exporter by value, follows as the leading exporter of high-quality saltwater Akoya pearls. Other major producers include Australia, the leading producer of white-lipped South Sea pearls, both Indonesia, and the Philippines (for silver and golden South Sea pearls), and French Polynesia (black/grey/green Tahitian pearls).

Consider buying loose pearls and having them set later at home, which can cost less than pre-made designer pieces in Tahiti and may save paying import duty.

Australian White-Lipped South Sea Pearls are typically the world’s highest value due to their large size (up to 18-20mm), longer cultivation times (2–4 years to produce their signature, thick nacre), greater rarity, and high-quality luster.

Philippine Golden South Sea Pearls are considered exceptionally rare, with deep 24-karat gold pearls being highly valued.

Indonesian South Sea Pearls are renowned for silver and gold, are generally competitive but often priced just below the top-tier Australian whites and deepest Philippine golds.

Akoya Japanese Pearls, typically smaller (usually 6mm–8mm, rarely up to 10mm), are considered more affordable, high-quality, mid-range saltwater alternatives.

French Polynesia (black/grey/green/peacock Tahitian pearls) produces the least valuable strata of saltwater pearls (up to about 14mm). In French Polynesia, Tahitian pearls must have a minimum nacre thickness of 0.8 mm; ask about nacre and avoid heavily treated or very thin-nacre pearls that will not last.

Both Tahitian and South Sea pearls require 16-24+ months, but the Pinctada maxima (South Sea) oyster is more sensitive to environment changes than the Pinctada margaritifera (Tahitian).

Chinese freshwater pearls are, for the most part, cultured pearls grown in mussels within Chinese lakes and rivers, making up over 90% of the global supply. Renowned for their durability (solid 100% nacre), wide range of natural pastel colors (white, pink, lavender), and diverse shapes, they range from affordable, irregular shapes to high-quality, large, near-round pearls. Modern Chinese freshwater pearl farming has improved significantly, allowing them to compete with, or sometimes replace, higher-priced saltwater pearls like Akoya, especially in terms of size and shape variety.

If you want the absolute best value for the strongest price to quality ratio:

Buy loose Australian pearls in Broom (where they are farmed), but pearl-based jewelry in Perth

Buy loose Tahitian pearls in Tahiti (lots of competition), but pearl-based jewelry in Bora Bora (big tourist market)

Locations to buy pearls in China:
Zhuji (Shanxiahu Town): Known as the "Pearl Capital," this is where most freshwater pearls are cultivated and processed. Pearls are often sold in bulk bags, and prices are the most competitive, making it ideal for wholesalers or serious buyers seeking the lowest, direct-from-farm prices.

Suzhou (Weitang): The Weitang International Pearl & Gem City in Suzhou is another major, highly affordable hub for freshwater pearls, particularly for high-quality items.

Beijing (Hongqiao Market): While not the production source, the Pearl Market (Hongqiao) in Beijing is famous for offering very low prices to retail tourists who are willing to bargain hard.

Shanghai (Hongqiao New World Pearl Market): A convenient location for tourists to find competitive, non-wholesale prices.

To save money, look for “seconds” or “near-gem” pearls with small surface flaws; these often offer the best price-to-beauty ratio for budget-conscious buyers. Remember, part of a pearl earing is often hidden by the ear and part of the pearl set in a ring or brooch is sometimes hidden.’’

There is a difference in the jewelry pricing philosophy in Europe compared to Asia. In Asia, it is considered normal to disclose the weight of the precious metal used as well as the gem stones, which makes it easier to negotiate based on the intrinsic value of a piece of jewelry. In the US and Europe, the “artistic value” of the piece is what ius promoted and you’ll possibly get astonishment and push-back if you insist on trying to find out the weight of the gold or silver used to create a piece of jewelry.

IMPORT DUTY?
Loose diamonds and other gem stones, natural pearls, and opals (for non-commercial use) can, in general (Russian diamonds are not exempt), enter the United States duty‑free (declare the purchase, but duty won’t be charged). On the other hand, jewelry with set stones (even if purchased in a duty-free shop aboard a ship or in an airport) are subject to duty and import taxes. Similarly, while gold bullion bars and coins are duty-free, gold jewelry is subject to duty taxation (currently at about 5.5%.

BUILDING JEWELRY
That means that we occasionally gems where they are mined and/or cut and bring them home. It may take years to become inspired and use them, but fortunately, we live an easy commute to NYC’s “Diamond Center”. We can either explain to a jeweler what we want and have him/her do the legwork or we can act like a general contractor and create the design and then have a goldsmith make the article (or, if it is a standard design, buy it from a findings/setting manufacturer), buy the gems from a diamond merchant, maybe others from a lapidary and them bring the items to a diamond-setter for assembly.

Key suppliers of findings and settings include Golden Casting, Myron Toback Inc., Ross Metals, Empire Casting House, and Crown Findings.

Lapidaries include NY Lapidary Service Inc and Majestic Lapidary

A reliable diamond merchant offering excellent goods at a reasonable price is David S. Diamonds