- L
-
- Lab
- Laboratory
- Labradoresce
- Labradorescence
- Labradorescent
- Laccolith
- Lamellar
- Laminated rock
- Lanthanides
- Lapidary
- Lattice
- Lava
- Lenticular
- Light
- Light refraction
- Light reflection
- Litmus paper
- Locality
- Lode
- Longwave
- Loupe
- Lubricant
- Luminesce
- Luminescence
- Luminescent
- Luster
- LW