The least tightly packed crystal structure.
Colourless, odourless, heavier-than-air gas. Necessary for the photosynthesis of plants.
Crystalline allotrope of elemental carbon, the hardest known natural substance.
The face-centred cubic metal lattice allows the closest fit of metal atoms.
A crystalline allotrope of carbon which was discovered at the end of the 1980s.
Metals forming hexagonal metallic lattices are rigid and difficult to machine.
The invention of the ballpoint pen made writing a lot easier.
A crystalline substance, an extremely important material in the electronics industry (semiconductors, integrated circuits).
A polymorphic compound, mostly found in the form of quartz.