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Polar Metals seeks to spice up your life with interesting and unusual metals in unexpected ways. We brought you some interesting exotic metals in our TIER I, now we are introducing you the unusual elements: Niobium, Tantalum, Hafnium, Rhenium, Thulium, Lutetium, and Scandium.    

Each cube is highly polished by hand for many hours to reach a mirror finishLaser engraved. Lasts forever. For true metal lovers!

Here are some interesting facts:

* Niobium (8.57 g/cm3): It got its name from the Greek goddess of tears Niobe. It almost always found side by side with Tantalum in nature, they are interesting "indispensable twins". It is physiologically inert and hypoallergenic, used in prosthetics and implant devices, such as pacemakers.  

Tantalum(16.69 g/cm3): It is one of the refractory metals. Its melting point is exceeded only by tungsten and rhenium. It's highly corrosion-resistant, wildly used in aircraft engines, capacitors and laboratory equipments. 

Hafnium (13.31 g/cm3): It is highly corrosion-resistant. It does not exist in nature on its own, but is combined with zirconium to form minerals.The low abundance and difficult separation techniques necessary make it a scarce commodity.

Rhenium (21.02 g/cm3): It has the highest boiling point ​(5630 °C, ​10,170 °F) and the third highest melting point (3186 °C, ​5767 °F) of any element, wildly used in jet engines. It is one of the rarest elements in the Earth's crust.

Thulium (9.32 g/cm3): It actually is the least abundant of the rare earth metals. It's is soft enough to be cut with a knife. It has a bright silvery-gray luster. It's very difficult to make, we spend several hours to just make one cube.

Lutetium (9.841 g/cm3): It is only available in the Earth's crust at about 0.5 milligrams per kilogram. Lutetium is not widely used. It only uses for specific purposes. It has the highest Brinell hardness of any lanthanide, at 890–1300 MPa.

* Scandium (2.985 g/cm3): It is difficult to isolate in its pure form. It wasn't until 1960 that the first pound of scandium was produced. It is more abundant in the stars where it is around the twenty-sixth most abundant element.


Size  10*10*10mm (0.39in)


    • Niobium:  8.57g
    • Tantalum: 16.6g
    • Hafnium: 13.3g
    • Rhenium: 20.5g
    • Thulium: 9.8g
    • Lutetium: 9.7g
    • Scandium: 2.8g

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