Don't mix apples and oranges when weighing karats

G

OLD, silver, jewelry and gems; the Russian Market, the Olympic Market, the Central

Market and numerous shops are a veritable shopper's paradise. Everything seems so

cheap. But are you getting what you pay for? Gem dealer and expert David Mead

provides some tips for those tempted by what's on offer.

THERE are many locally mined gemstones in Cambodia. The most precious is the ruby

followed by sapphires colored from blue through green to yellow. A so-called "cornflower"

blue sapphire of good cut and color is an exceptionally beautiful local gem.

Some of the other semi-precious stones from Cambodia include Blue Zircon (in its

natural state, brown), Peridot, Amethyst, Spinel and there are literally buckets

of Garnets (mainly browns and reds). Diamonds are not found locally.

The quality of cutting gemstones in Phnom Penh is generally up to international standard.

If, for a particular setting, you want your stone re-cut, say from oval to round,

you can have it done for a few dollars or in most cases within the price of the cost

of the stone. Of course you will pay for the carat weight of the stone before you

have it re-cut.

For estimating the price of your jewelry when it is made of gold or silver plus gemstones,

note that one carat of gem weighs .2 grams.

In bracelets or necklaces which contain large numbers of small rubies or sapphires

it is likely the stones will be natural (real). But many stones will not be clear

(or clean) and you will not be able to see through some of them because they are

heavily flawed internally. Of course these type of stones will be cheap and the flaws

not a problem unless they detract from overall appearance. However, what you must

look for are any stones that are cracked right through or that sit loosely in a setting,

because, particularly in a bracelet that is to be used every day, the stones may

fall out.

As it will be difficult to see the cracks with the naked eye, I suggest the best

investment you could make, if you shop regularly for jewelry, is to buy your own

10-power triplex loupe (a special magnifying glass).

You can get them at jewelry and stone supply shops around town for about $20.00.

Hold the loupe close to the eye and bring the piece/gemstone towards it. When checking

a gem for inclusions (flaws), look through the back of the stone. Also use the loupe

to magnify the spot that you have filed to check for plate.

Another tip, regularly check your jewelry for chips or cracks in the stones or for

loose settings. If you find a problem, take it back to the jeweler. They should fix

loose settings and may even replace cracked stones for free.

A simple way of cleaning your jewelry is to use an old soft toothbrush and some liquid

detergent. If it is really dirty, toothpaste will do the job.

Good sized rubies and sapphires are available in Phnom Penh but be very careful.

Never buy a stone from the itinerant trader types. They are usually accompanied by

an interpreter and often claim the stones come from Pailin.

The town is full of synthetic stones and there are many less than honest jewelers

about. Synthetics are stones produced in a laboratory and have the same chemical

composition as the natural gem.

If a stone is cheap and flawless it is likely to be synthetic. Almost all natural

gemstones will have some minor flaws e.g. a small speck of iron or a wispy feather

looking inclusion.

The difference in value between the two stones is substantial - for over 2 carats

of natural ruby of the finest quality and color you could expect to pay up to $3,000,

if it is synthetic, it may be worth $10 (provided it is well cut!).

As a general rule, for one carat of the best quality ruby expect to pay up to $650,

for the same weight of blue sapphire $200, for green or yellow sapphire up to $100.

Other "semi-precious" local stones are far cheaper, but generally up to

$10 for one carat.

As you will have noticed from the ruby example, large gemstones become far more expensive

per carat weight as the size/weight increases. Cost is also influenced by how many

flaws the stone contains, by its color and brilliance and to a degree by its cut,

e.g. the stone may have little depth, perhaps suitable in a pendant but not in a

ring. Cost can vary dramatically when these factors are taken into account.

When buying stones always take them outside to look at color, clarity and brilliance

in direct sunlight. Also, balance the stone between your fingers and imagine what

it would look like in a ring. Is the stone flat or dull looking or is it like some

"cornflower" blue sapphires you will see, where brilliance and color are

dazzling?

How can you tell if the stone is natural? Without the right equipment and practice

you can't! Additionally, salesmen and/or jewelers may try to sell you something that

is not what it should be, e.g. a red Garnet or a red Spinel as a ruby. The Garnet

- perhaps $5 a carat; the Spinel - perhaps $40.

I recently went into a large plush souvenir store on Mao Tse Tung Blvd resplendent

with cases filled with stones which the staff claimed to be rubies and sapphires.

Ushered into an inner display room where perhaps the more natural stones lay, I picked

a four-carat, $1200, so-called Ruby for closer examination.

Even without equipment, I adjudged it to be a Garnet and offered $12 for this clean

pinkish-red stone - the offer was not accepted.

The key give away was the price - if it had been a natural Ruby then the bidding

should have started around $10,000.

And it is not just casual shoppers who are fooled. The large red stone in the English

Imperial State Crown, the so-called "Black Prince's Ruby" is in fact a

Spinel.

The lesson: only buy from a jeweler who gives a written guarantee to refund your

money if the product is not what it purports to be. Ask friends who have been here

long enough to have their jewelry and stones tested which jewelers they trust.

In addition to gems there is plenty of gold and gold jewelry on offer and the first

consideration here is its purity.

Pure gold is 99% gold and is described as 24 karat (karat: same pronunciation but

different spelling as the unit for gem weight), 18 karat is 75%, 12 karat is 50%

gold and so on.

The gold is mixed with metals such as silver and copper to produce the alloy mix

that then becomes the total weight of the item, which is measured in grams. The metals

added also contribute to producing the color of the gold, i.e. yellow or rose gold.

So how is it possible to test if the gold on sale is the number of karats (with a

K) claimed? Simply, you can't, unless you have acid testing equipment in your pocket

- not really advisable.

Generally it would not be unusual for your 18 karat piece to test 15 karats or for

15 karats to test 12 karats in Phnom Penh.

But while it is difficult to check for purity, it is very easy to check if the piece

you are interested in is gold plated rather than solid gold.

For this an emery board is the ideal tool. Take the piece of jewelry (with permission

of course) and file into one spot, (obviously at the rear of the piece) and see what

lies underneath. If you see a distinct change in color, probably to a copper color,

then the item is likely to be gold plated and the plate probably only 9 to 12 karats.

In the markets you will generally pay for gold jewelry by weight in grams plus a

percentage for the labor, so always have the item weighed.

Expect to pay (currently) from $6 to $10 per gram depending on the percentage of

gold (karatage) plus, as a rough guide, about 10% for labor.

So if you find a 50 gram 12 karat gold chain on sale for half of the approximate

$350 you should expect to pay, it's likely to be plate. Particularly look for plate

in light gemstone necklaces and bracelets.

Silverware is also in abundance in Phnom Penh's markets but that silver elephant

or those wonderfully Khmer decorated serving spoons and ladles may not be what they

appear to be. If it is marked 50% silver then it will only be silver plate, usually

on a brass or copper base.

The item is produced in the base metal and then dipped. As long as you know it is

plate the product is fine, but you must keep it away from the dishwasher or for that

matter silver polish.

Just wash local plate in soap and water and polish it with a soft cloth. If the brass

does show through, you can buy silver dip or silver converter to renew the silver

color. Some silver sellers will sell you a local product equivalent.

Although gold may be described by "fineness" in parts of 1000, it is more

usual that silver is described that way, i.e. 800 or 900 silver, or by a percentage

as we find in Phnom Penh. I've talked about what generally constitutes 50% here (silver

plate), but you will find so-called 70% and a lot of silver marked 90%. The purer

the silver, the dearer it is and generally the softer it is, i.e. cutlery items will

easily bend in your fingers. Again, there are acid tests, but it is easier to go

back to the emery board and the underside of the item to test for plate.

If you file to a change of color (brass or copper) the answer is obvious.

Price is also an excellent test of the quality/fineness of silver pieces. For 90%

silver you will pay a minimum of $25 per hundred grams. If the price is less it is

most unlikely to be 90%.

As an aside, the weight of 18 karat gold is about one and a half times heavier than

the weight of pure silver of the same volume. So when you ask a jeweler to copy a

100 gram silver chain in 18 karat gold, the same size chain will need to be 150 grams

in weight. The copying skills of goldsmiths and silversmiths in Phnom Penh are generally

excellent and most of the time a good picture will suffice for a quality copy to

be produced. If you're not happy with the result don't pay until the product is as

you want it.

In summary, remember rule one: if you cant get a "money-back" guarantee,

don't buy!