Simple metal containing carbides and nitrides

There are few/no natural mineral examples for these compounds.
This is likely because all these compounds are in a highly reduced stated and some of them are
not even capable of forming a protective macroscale passivation layer.

Awesome compounds

Titanium:

• TiC Titanium carbide – and ZrC Zirconum carbide
• TiN Titanium nitride

Silicon (counting silicon as metal here):

• SiC Silicon carbide
• Si₃N₄ Silicon nitride [1]

For more awesome compounds see: Base materials with high potential

Compounds that need to be sealed in PPV to be usable

Iron:

• Fe₃C Iron carbide aka cementite aka iron cohenite – ortorhombic – Mohs 5.5 to 6.0 – 7.20 to 7.65g/ccm – metallic luster
• Iron nitrides – Wikipedia: "Group 7 and group 8 transition metals form nitrides that decompose at relatively low temperatures" Fe₂N 400°C

Aluminum:

• Al₄C₃ Aluminum carbide [2] – hydrolyses in contact with water
• AlN [3] – hydrolyses in contact with water – it's a diamond like compound (a III-VI semiconductor) – highly covalent character

Calcium:

• CaC₂ Calcium carbide [4] – must be kept dry – releases ethyne on contact with water
• Ca₃N₂ calcium nitride [5] – highly reactive with water

Magnesium:

• Mg₃N_2(s) Magnesium nitide [6] – reacts with water
• Magnesium carbide ??

Compounds with more rare elements

Nitrides:

• CrN – Carlsbergite (mineralienatlas) – Mohs 7
• VN – Uakitite – Mohs ??

Carbides:

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4th period:

• Various chromium carbides: Chromium(II) carbide
• Cr₃C₂ – Tongbaite (wikipedia (mineralienatlas) – Mohs 8.5 – ortorhombic
• Cr₃C₂; Cr₇C₃; Cr₂₃C₆ (1,895 °C; 3,443 °F; 2,168 K; extremely hard; very corrosion resistant)
• VC (2810 °C; 9-9.5 Mohs, cubic)

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5th period:

• ZrC (3532 °C; extremely hard; highly corrosion resistant; very metallic, cubic)
• Nb₂C (3490 °C; extremely hard; highly corrosion resistant)
• Mo₂C (2692 °C) [7]; MoC; Mo₃C₂ [8]

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6th period:

• WC – Qusongit (mineralienatlas) – Mohs 7.25
• HfC (3900 °C; very refractory; low oxidation resistance, cubic)
• TaC – Tantalum carbide (mineralienatlas) – Mohs 6-7 – tantal is very rare

Borides:

• OsB, Os₂B₃ and OsB₂ – Osmium borides
• ReB₂ Rhenium_diboride

Related

• Refractory compound

External links

• Superhard material
• Category:Superhard_materials