At the Base of the Mountain

A sandy, one-lane road leads from the national highway to the base of the mountain where faceted topaz is sold. A military-style checkpoint monitors a drop gate over this road a kilometer short of the mountain, but checking through there is quick, a simple formality, and nothing in the pleasant interchange reveals the purpose of the facility!

Cars can easily make the five-kilometer drive in, if the weather is dry, and motorbikes have very little problem except for the parts of the road where the white sand is at its thickest, back wheels can slough and spin, but if you are using a local driver, no worries. They are experts.

A dozen women have set up shop at the base of the mountain, there is plenty of parking and shade. Their display cases are glass and metal, but their 'stores' are bamboo, slim-cut timber with sugar palm foilage on the roofs. What you would see anywhere in rural Cambodia.

All of the stones are very clear, with limited inclusions, many are colorless, some with a hint of yellow (see the stones at the head of this blog). As you would expect with 'raw', untreated (but faceted), natural Topaz -- the stones are brilliant (in the past they have been mistaken for diamonds, see for example, the Portugese 'Braganza Diamond').

One should be aware of that the displays present topaz and quartz both of which come from the site. The smoky topaz and the smoky quartz may be difficult to differentiate, except that topaz 'feels' heavier (compare stones with similar volumes, the carat weights should differ), its specific gravity is 33% greater than that of quartz (approximately 3.5 versus 2.6). To me, topaz also has a kind soapy feel, quartz a glassy look and feel (but that is very unscientific).

If you are unsure of your own differentiations, you need not worry, I believe that these dealers are honest, They know the price they will all pay if word of mouth indicates that they are cheating customers. They are fully aware that the hardness of Topaz is greater than that of quartz, for them differentiation is easy, as they sub-contract the cutting. If the lady says that it is Topaz, you can take it to the bank.

There is a very wide range of cut stone sizes, with some very large ones available. But it in this case size is not necessarily better, hard to know what to do with a 50-carat cut topaz! And with prices between $5 and $10 per carat, total costs can mount quickly. And if you are used to cut citrine or amethyst, a five-carat topaz will seem somewhat small -- again its density is greater than quartz.

The lady in the picture above was the first one to show me what they all call blue topaz. The color of all the stones that I saw was blue-green, a sea-green, as the Khmer has it (poa duk samot - seawater color). The saturation of the color varies from stone to stone, but the most deeply colored are still very light.

When I was told that the stone was a natural blue topaz, my initial reaction was disbelief, disbelief out of my own ignorance. On returning to Phnom Penh I turned to the trusted Handbook of Gem Identification (Liddicoat, GIA), and yes, there are naturally occuring Topaz gemstones that are blue, but their commercial value is low since much more saturated colors are easily available from heat-treated and irradiated natural stones.

Back at the bottom of the mountain, another lady sitting with the seller I was speaking to, bashfully whispered 'aquamarine', which I did not know what to make of, since I knew little about the stone.

I aimed to learn more. Aquamarine would be interesting. If Topaz is more valuable than Quartz, though both are very common, good faceted Aquamarine is significantly more valuable than Topaz.

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Takeo Province - Cambodia's Topaz Mines

Takeo is the name for both the Cambodian Province and for its Provincial Capital. Takeo town: roomy, uncluttered, quiet and slow; it is about an hour's drive from the Vietnamese border.

The Province is located in the midst of the flat, rainy-season flooded Mekong Delata. As you can imagine, rice growing is very important to the local economy, and with all of the water, so is fresh-water fishing. A stay in Takeo would not be complete without sampling the fresh water shrimp, big and sweet, and unfortunately, increasingly expensive.

In the town itself there is little sign that topaz gemstones are an important part of the local economy. In a visible sense, they are not. Not the way that sapphires rubies once were in Pailin Province, or that Zircon still are in Ratanakiri Province. You walk up the main streets in both Provincial centers and you see lots of shops But in Takeo there are middlemen and women who have shops in town, shops for both the cut stone and for topaz gem rough. And at the base of the mountain where the mines lie, near the Vietnamese border, an informal set of shops have set up business.

I had visited the town about two years ago with a good friend of mine who (with his wife and children) run a jewelry counter at Psaa Toul Tompoong (Russian Market) in Phnom Penh. The stones that I saw then were beautiful. A lot of clear, clean, colorless Topaz was being found and cut on the mountain and sold at its base; if you wanted rough, you could buy that in town, but you had to know where to go, as my friend did.

What brought be to town this time was the rumor that light-shaded blue topaz was being sold. Though I have studied gemstones (colored stones mainly) at GIA Bangkok and at AIGS, I thought that the color of blue topaz was only a product of heat treatment and irradiation (as the deep blues that we typically see in jewelry shops are); I thought in short that there are no natural blues. It turns out that there are naturally blue stones found at mine sites (very light colored ones), but the blue stones found in Takeo are something entirely different as this series of blogs will reveal!

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Topaz Rough From Cambodia

Tako Province is south-east of Phnom Penh, not even one hundred miles. National Highway Two runs to the Vietnamese border-crossing south of Takeo Provincial Town at Phnom Denh. If you look at a satellite map of Takeo Province you can see where Route 2 crosses into Vietnam. Just before the crossing is a mountain west of the road reduced dramatically by quarried dirt, stone and clay 'stolen' for road projects; that is Denh Mountain. Just north of that is another mountain, same side of the road no name on the map, but home to Tonleab Village. Its interior is relatively unmarked by tree cutting or cropping. It is on this mountain that Topaz was discovered about ten years ago. Digging sites are a five kilometer climb into the interior of the mountain: an hour to an hour-and-a-half! Gem sellers sell cut gems at the base where the dirt road from town (Kampong Chrey) leads to a very nice recreational area with mountain streams, swimming hole -- with a moutain backdrop.

Above is a picture of four pieces of Topaz rough. The crystals are pitted from their journey to their final resting place, the mostly clay soil of the mountain. But Topaz is quite hard, measures at 8.0 on the Mohs scale, softer than Rubies or Sapphire (9.0) and diamond (10.0).

It is also one of those gemstones, like amethyst and citrine, or zircon, which are often found in large pieces without major inclusions. The crystal forms in Orthorhombic system. Geologists call its crystal habit 'prismatic'. The vast majority of the stones that are cut for sale are clear or have a light yellow or brown tint. There are stones being dug from the top of this mountain that are very light blue but the gem sellers at the base of the mountain are not certain whether it is blue topaz which they have cut and are selling. One lady whispered aquamarine to me. (We will pursue this question in another post :).

The stone above was photographed in early morning light, even though it is pitted it is translucent enough to glow with the rising sunlight that backit it.

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