Tellurium is a non-metallic element with many properties similar to selenium and sulfur. It is silvery-white and lustrous in solid form and dark grey in powder form. Tellurium’s industrial uses include, as an additive to improve the machinability of steel and copper alloys, as a catalyst in chemical processes and in the manufacture of rubber. It is a p-type semiconductor and its conductivity is sensitive to light exposure. Tellurium compounds (tellurides) are semiconducting materials and used for photoreceptors in copiers and solar cells. Tellurium is soluble in sulfuric acid, nitric acid, potassium hydroxide and potassium cyanide solution. It is insoluble in water.

Crystal Structure: Hexagonal; at 25 ^oC, a = 0.44565 nm and c = 0.59268 nm.

Density: 6.237 g/cm³ at 25 ^oC. Temperature dependence:

               solid (0 to 450 ^oC), ρ = 6.250 - 0.000261 T

               liquid (450 to 1000 ^oC), ρ = 6.170 - 0.000777 T.

Boiling Point: 989.8 ^oC

Coefficient of Linear Thermal Expansion: 18.2 µm/m ⋅ K at 20 ^oC

Specific Heat: 0.201 kJ/kg ⋅ K at 25 ^oC

Latent Heat of Fusion: 86.113 kJ/kg

Latent Heat of Vaporization: 446.43 kJ/kg

Thermal Conductivity:Polycrystalline, between 5.98 and 6.02W/m⋅K at about 20to28 ^oC.

                                    Single crystals, 3.3 W/m ⋅ K ∥ to c axis, 2.1 W/m ⋅ K ⊥ to c axis.

Electrical Resistivity: Polycrystalline, between 1 and 50 mΩ ⋅ m at 25 ^oC.

                                    Single crystals, at 20^oC: 5mΩ⋅m ∥ to c axis, 1.5mΩ⋅m ⊥ to c axis.

Magnetic Susceptibility: At 18 ^oC, -39.5 x 10^-6 in cgs units

Tensile Strength: Approximately 11 MPa

Hardness: 25 HB, 2.3 Mohs

Elastic Modulus: Tension (single crystals): 42.57 GPa ∥ to c axis

                                                               20.45 GPa ⊥ to c axis.

Shear: (Polycrystalline), 15.16 GPa

Liquid Surface Tension: 186 mN/m at 450 ^oC