Gemstones (original) (raw)

It is quite common for travellers to buy gems or finished jewellery during a trip. Often price and selection are better in places where stones are mined, cut or set than elsewhere. Caution is required since some vendors are positively predatory, especially in tourist areas. Bargaining is often needed to get a good price, even from an honest vendor.

It does not always apply, but the phrase "touchstone markup" is used in the gem trade. That is a 100% markup; the price will double for every set of hands the stone passes through. Sometimes this means that the price difference between buying at or near the source and buying elsewhere is enormous.

As with any goods that span a wide range of prices, it is safer to avoid the big-ticket items unless you are either an expert yourself or have expert advice, dealing with a large reputable vendor will reduce the risk, and "tourist trap" stores should be avoided. See shopping for other general advice.

Some travellers also dig up gems themselves; see Rockhounds.

Stones are sometimes classified as precious (diamond, ruby, sapphire and emerald, perhaps plus a few others) or semi-precious (everything else) and prices generally reflect this, though some semi-precious stones are also quite expensive.

If you plan to bring home expensive jewellery, check your country's import regulations. Some countries, such as Canada, charge a stiff duty on finished jewellery but much less on unmounted stones. In those cases it may be better to buy cut and polished but unmounted stones and have a craftsperson back home mount them. Sometimes it is possible to bring some extra stones and trade them for the labour.

A few decades back some travellers did quite well importing stones from places they had visited into their home countries. Gems can easily be shipped by registered mail and in many places the local silversmiths would happily buy them. However, this is much less likely to work well today since the smiths can now just buy directly from foreign vendors via the web.

Both the quality and the size of stones can greatly affect their price; stones that are large, flawless or both may be rare and expensive.

Topaz in various colours

Colour is often a factor; many gems come in a range of colours, depending on which impurities are present. Murkiness, inclusions (other minerals within the stone, often giving dark or opaque areas), or flaws can greatly reduce the value of a stone. Pointing these out may be helpful in bargaining.

Stones are generally priced by weight, measured in carats; five carats is one gram. Within the range of common sizes, the weight/price relation is linear; if for some gem a 1-carat stone is 10thena10−caratstonewillbeabout10 then a 10-carat stone will be about 10thena10−caratstonewillbeabout100, provided such stones are reasonably common. However if stones above 5 carats are rare, then a 10-carat stone may be considerably more than $100 and the price of a 20-carat stone is likely to be astounding.

Stones that are two or three of large, flawless and of beautiful colour can fetch astonishing prices; they are often sold at auctions where only museums and millionaires can afford to bid. The record price for sapphires, as of 2025, is US$8.4 million for a pair of earrings, for emeralds about the same for a ring. The records for rubies and diamonds are considerably higher.

If one stone is just a scaled-up version of another (multiply length, width and depth by the same constant), then the volume and weight are proportional to the cube of the diameter. A stone that is twice the diameter of another will then be about eight times the weight and at least eight times the price. Of course this is not always the case; a larger stone may be cut proportionally thinner than a smaller one.

Several smaller stones in a piece of jewellery may be a better buy than one large one; it is common to see three sapphires in a row across a ring or one moderately large stone with several smaller ones around it. For example, three stones of 5mm diameter will usually have total weight, and therefore cost, considerably less than a single 8mm stone (3*53 = 375 is less than 83 = 512), but the total surface area they display will be slightly larger (3*52 = 75 is more than 82 = 64). Also, smaller stones are less likely to be seriously flawed; a cutter working on a raw stone that has a flaw might either produce a large but flawed finished stone or cut around the flaw to get several smaller unflawed stones.

The Mohs scale measures how resistant the gem is to scratching. This scale uses various minerals to define its levels; the top four are diamonds 10, corundum (sapphires and rubies) 9, topaz 8, and quartz 7. These are hard enough for any use; in particular they can be used in a ring with no fear of damage if the hand bumps against something. Other hard stones — such as beryl including emeralds (7.5–8), spinel (7.5-8), tiger eye (7), tourmaline (7-7.5) or garnet (6.5–7.5) — can also be used anywhere.

The Mohs hardness scale

Rose quartz, clear "rock crystal", citrine (yellow or brown) and amethyst (purple) are varieties of crystalline quartz with different colours from different impurities; all have hardness 7. Agate and jasper are largely quartz and have hardness 6.5 to 7.

Moderately hard stones – moonstone (6-6.5), opals (5.5–6.5), turquoise (5–6), labradorite (6–6.5), sodalite (5.5–6), diopside (5–6), lapis lazuli (5–6) and obsidian (volcanic glass, non-crystalline quartz) (5-5.5) – are less than ideal for rings or bracelets. They are fairly often used in those, but there is some risk they will scratch, chip or crack if they hit something. It is safer to get them in some other piece of jewellery; earrings and pendants are popular choices. The shape of the stone and the design of the setting affect the risk; a stone that sticks out is much more likely to be damaged than a flat one or one protected by the setting.

Stones with hardness below 5 should be used only where they are unlikely to get banged about, in particular never in rings. Examples include flourite (4), pearls (2.5–4.5), coral (3–4), malachite (3.5–4), rhodochrosite (3.5–4) or amber (2–2.5).

Toughness on the other hand, is how resistant the gem is to breaking. There are four rankings; poor, fair, good, and excellent.

Jadeite, nephrite are ranked excellent; quartz, tourmaline and diamond are ranked good; topaz, apatite and fluorite are ranked fair; while emerald, talc, and zircon are ranked poor.

Cutting and polishing

[edit]

Volcanic amethyst geode

Most gems are polished, though a few may be displayed just as they are found. Geodes – rock cavities lined with pretty quartz crystals – are generally sliced open for display but do not need polishing.

Many rockhounds use a tumbler. Non-gem stones and chunks of glass are commonly tumbled and sold for use in aquariums or gardening; these are quite cheap compared to any sort of gem. Tumbled gems are also usually cheaper than other gems.

Both in tumbling and in other polishing a series of abrasives are used, each finer than the last.

Stones which will be used for jewellery are generally cut and polished. Some are tumbled, some are just polished in their natural shape – for example the Black Prince's Ruby among the British Crown Jewels – and some polishing occurs naturally, as with Lake Superior agates, which are polished by wave action. But most are cut, either with facets or in a smooth curve, and then polished.

Cabochon tourmalines

Some stones – such as jade, pipestone (e.g. Pipestone National Monument), alabaster (e.g. Fuzhou#Shoushan stone), soapstone (e.g. Ouro Preto#Soapstone market or Kuujjuarapik#Buy) and marble (e.g. Dali#Buy) – are used in large pieces for carvings. These are also usually polished.

Gems are found all over the world, but some places are famous for certain types. Sites such as Gem Society have details for over 300 gemstones and Wikipedia also has a list. We list some of the most important below, in alphabetical order.

Agate

Black star diopside

Babylonian seal, 6-7th century BCE, Lapis lazuli

Moonstone

A Coober Pedy opal

Tiger eye

A few types of gemstone are found only in quite limited areas. They are likely worth looking for if you travel there.

Ammolite

See paua shell below for an item found only in New Zealand.

Rubies and sapphires

[edit]

Rubies and sapphires are the same mineral, corundum (hardness 9); different impurities give different colours. Red ones are called rubies; any other colour is a sapphire, but the most prized sapphires are intensely blue. Top-grade stones are very clear and can be cut with facets; lesser stones are cut cabochon to give star rubies or star sapphires.

Star sapphire ring

Sri Lanka is known for sapphires, Myanmar (Burma) for rubies, but both of those countries and India have some of each. There are also rubies in Greenland and Nunavut.

Off-color stones – most commonly grey, but also burgundy, pale blue, pink or brown – are much cheaper than bright red or blue stones and may still be lovely. Burgundy "plum stars" are common in Agra; they usually have a lot of inclusions (about a third of the stone is black), but they can be quite pretty and are remarkably cheap compared to other rubies. Sri Lanka has many grey star sapphires, also relatively cheap.

Black, green or purple star sapphires are rare and command a high price; they have a six-point star like any other sapphire. A "black star" which has only four points is a semi-precious stone called diopside, and should be far cheaper. Some vendors may try to sell tourists diopside black stars at sapphire prices; walk away quickly.

Historically, some red spinels were also called rubies, but gemologists now reserve the term "ruby" for red corundum.

carved jade pendant

Jade has been an important stone in many cultures throughout history. It is used not only in jewellery, but also in carvings, statues, tools, weapons and even for household objects like bowls. The Liangzhu Culture in China (3400–2250 BCE) is known mainly by the high-quality jade artifacts it left behind, and many other groups – especially in other parts of China, Southeast Asia, Mexico and Central America, and the Maori of New Zealand – used jade.

There are two distinct minerals that are called jade; nephrite is more common, jadeite often more valuable. Most Chinese and all Taiwanese and Canadian jade is nephrite; most Burmese and Mexican jade is jadeite.

Taiwan still produces jade, with much of the mining being concentrated in the area around Hualien, and numerous jade shops in the city.

There are still some good Chinese sources for jade, notably Khotan, but today most of the jade in China is imported from Myanmar (Burma). The border town Ruili has much jade, but for the best deals, go to Myanmar.

In Myanmar, the city of Mandalay has a jade market where you can watch merchants haggling over the price of jade at all stages of production. You can even purchase some jade trinkets yourself, but be prepared to haggle, and if possible do some homework beforehand to have some idea of what prices should be.

British Columbia (Canada) is also famous for jade; the sprawling Jade City store on the Stewart-Cassiar Highway in northern BC is a great experience for jade fans, but you can find better deals in Vancouver.

There are other stones which may be used instead of jade, including serpentine or "false jade" and "greenstone", a general term applied to several different minerals.

Fuzhou has the Yutian Ancient Chinese Jade Museum.

A pearl necklace

Almost every tropical seacoast area has some pearls, hard objects produced by various aquatic mollusks. Places known for their pearls include Tahiti, Bahrain, Mexico, India, Indonesia, Myanmar and the Philippines.

Pearls are not hard enough for all applications; the most common uses are in necklaces and earrings. Good pearls are not cheap, but they are much less than some other gems; a fine pearl necklace will be expensive, but one with the same number and size of emeralds might bankrupt a small country.

The best-known type is produced by various species of oysters and made of a substance known as nacre or mother-of-pearl, giving it its distinctive iridescent appearance. Natural pearls are rare and expensive; the vast majority of pearls on the market today are cultured pearls, made using a technique which originated in Japan but is now used in many other countries.

China has freshwater pearls, made by a species of freshwater mussels, and usually cheaper than saltwater pearls. These are also made of nacre.

There are several types of pearl not made of nacre:

Unlike oyster pearls, these have never been cultivated, so they are rare and expensive.

Paua shells

"Mother-of-pearl", the lining of mollusk shells (including some from species that do not produce pearls), is also used in various decorative arts including jewellery. Large pearls are rare and expensive, but it is relatively easy to get a large chunk of mother-of-pearl; just find a big shell and cut it to suit the requirement.

Mother-of-pearl is often used in inlay work on furniture or other household items. In China, wooden Go boards with mother-of-pearl inlay for the lines are fairly common.

Map

Map of Gemstones

Almost any natural history museum worldwide will have a geology section, often including some gems. Some mines and many mining towns or regions also have museums with gems.

Many museums have shops selling high-grade replicas of items in their collections, and these are often excellent sources for jewellery. Major institutions like the British Museum or the Smithsonian have very fine shops, and other museums often have good ones.

There are also online stores such as The Museum of Jewelry and The Museum Company that sell replicas of historic jewellery.

Imperial State Crown
Black Prince's ruby above Cullinan II
Saint Edward's Sapphire near top

Some famous gems are in museums:

Hope Diamond

Both the Uncle Sam and the Canary Diamond were found in a mine which is now Arkanas's Crater of Diamonds State Park where visitors can search for diamonds.

There are two important ethical concerns you might consider in regard to buying gemstones.

The first is the destructiveness of mining practices. For example, some diamond mines are of the open pit variety, which can cause irreversible environmental damage. In other places, mine safety is a serious problem. Some gems, such as quartz, may be mined by families digging deep in the dirt without any safety equipment or any way to prevent the tunnels from collapsing. What they dig out is usually sold for a pittance to distributors, who then sell the stones at a much higher price to wholesalers and tourists. Mines are often left unsealed and consequently, extremely dangerous to amateur miners who move in hoping to find gemstones left behind.

The second is that the value of the gemstones has made mines attractive to corrupt governments, terrorist groups and criminal organizations that use the profits they receive from the sale of these stones to finance private militias, bribes and extravagant life. For the countries in question, this often prevents a development towards rule of law and real democracy. Locally, the mining business often includes brutality, torture, murder and other crimes against humanity, to suppress protests. There have been some efforts to combat what are called blood or conflict gemstones and diamonds, but due to the lucrativeness of the industry, these are often smuggled across borders and find their way onto the markets of wealthy countries, anyway.

You should avoid wearing gemstones and crystals with magnetic charges if you have implanted medical devices such as pacemakers and defibrillators as they may interfere with these devices. Magnetic gems include magnetite, hematite, shungite and pyrrhotite. Watch out for any stone which contains iron.

Working with some gems can be hazardous. Malachite, for example, contains mercury and can emit dangerous fumes when being cut or polished. Like any heavy metal poison, mercury generally causes no obvious immediate symptoms but it remains in the body indefinitely and can cause long-term damage. Both digging for the stone and wearing malachite jewellery, though, are entirely safe.

This travel topic about Gemstones has guide status. It has good, detailed information covering the entire topic. Please contribute and help us make it a star!