Across
1
Precious yellow metallic element
3
Smallest unit of an element
7
Path of a planet around the sun
9
Blocking of light by a celestial body
10
Preserved remains of ancient life
11
Particle of light
Down
2
Chemical element in table salt
4
Mass per unit volume
5
Gas essential for breathing
6
Solid with repeating atomic pattern
8
Glass that splits light into spectrum
12
Naturally occurring inorganic solid