by Tom Mason

LUTETIUM TANTALITE – IT’S A mouthful for sure, but it’s also a particularly useful compound. The fact that lutetium tantalite is the most dense stable white material known to exist makes it ideal as a phosphor substance – the material that glows on the hands of an alarm clock or a glow-in-the-dark Frisbee. And it’s just one of the reasons why an extremely rare element called tantalum is becoming such a hot commodity.

Tantalum has some unusual qualities that we have only begun to appreciate in recent years. For one thing, tantalum electronic capacitors are the thinnest and most efficient known, making it an indispensable component for the electronics industry. In fact, every laptop computer, cell phone and Gameboy contains tiny tantalum capacitors.

The element is the only known metal that the human body will not reject, making it an important component in artificial joints and surgical implants.

Tantalum is virtually immune to corrosive attack by acids and liquid metals, a very appealing property for chemical manufacturing and heating elements. With a melting point of nearly 3,000 degrees C, it is sought after for use in heat shields, heating elements, industrial furnaces and other high temperature applications. It provides an excellent heat transfer surface, especially in harsh corrosive environments. And it is one of the most ductile, workable and weldable metals known.

Tantalum was first discovered in 1802 by the Swedish chemist Anders Gustaf. Because the element wouldn’t dissolve in acid, Gustaf named it after the Greek mythological character Tantalus who was doomed forever to stand in water that he could not drink and under fruit trees he could not reach. (The myth is also the origin of the word “tantalize.”) Originally dismissed as an impurity in tin, tantalum is about the same order of rarity as uranium. It’s that rarity, along with the sudden increased demand in the wake of the computer age, that have prospectors and mining companies taking a hard look.

Because tantalum is so valuable, it doesn’t take a large ore body to constitute a commercial deposit. In fact, quantities in the order of 200 parts per million — a few grains peppered through the bedrock — have major commercial potential. That’s good news for the environment as well. The small concentrations produce mines with small footprints that don’t have much impact on the surrounding landscape. In fact, a deposit less than an acre in size can be commercially viable.

As demand for the metal increases every year, tantalum mines are appearing around the world — in Australia, east Africa, China, Ireland, and western Canada. Even isolated Greenland is being explored for a possible mine. When commercial tantalum deposits are discovered , small companies or individual prospectors usually reap the initial rewards. Large mining companies don’t spend a lot of time exploring for minerals anymore, leaving it up to smaller firms who usually stake claims and then sell the mineral rights to large operations. That makes rare metals ideal for speculative investors.

Here are some other rare metals worth an investment look:

Beryllium: Lightweight metal alloys ideal for the aerospace industry, including space vehicle frames, heat shields and rocket engines. Beryllium is also useful as a moderator in nuclear reactors, in non-crystallizing springs and x-ray tube windows.

Cesium: A vital component in futuristic products such as magneto-hydrodynamic power generation, ion propulsion motors, opto-electronics (night vision glasses), chemical catalysts and DNA separation. Cesium is also an important part of calibrated drilling muds used in the oil and gas industry.

Gallium: Used in laser diodes, solar power cells, fibre optic components, computer hardware and electronic signal processors.

Lithium: Already well known as a component of batteries and pharmaceuticals, lithium is also important in host of other products including ceramics, glassware, glazes, enamels, metal alloys, chemicals and vitamins. It’s used extensively in the aluminum smelting and nuclear energy industries too.

Rubidium: This soft and highly reactive metallic element is used in the ceramics industry and may also have potential as a fuel for ion-drive space vehicles. A slight radioactivity makes rubidium useful as a medical radiological agent.