M
 
Macrocrystalline
Mafic
Magma
Magmatic
Magmatite
Magmatite rock
Magnesia
Magnet
Magnetic
Magnetic field
Magnetism
Malleable
Mammilary
Mantle
Massive
Matrix
Melting point
Mesothermal vein
Metal
Metallic
Metallic (luster)
Metallic elements (subgroup)
Metallurgy
Metamict
Metamiction
Metamorphic
Metamorphic rock
Metamorphism
Metasilicate chains
Metasilicate rings
Metasilicates
Metasomatically
Metasomatism
Metastability
Metastable
Meteor
Meteoroid
Meteoric
Meteorite
Mica
Mica group
Micaceous
Microcrystalline
Micromount
Mine (noun)
Mine (verb)
Miner
Mineral
Mineral group
Mineral series
Mineral show
Mineraloid
Mineralogy
Mineralogist
Mining
Mixed crystal
Mohs hardness scale
Molecule
Molecular
Molecular arrangement
Molecular structure
Mollusk
Molten
Molten rock
Molybdates (group)
Monochromatic
Monoclinic (crystal system)
Monotropic
Mother-of-pearl
Mother-of-pearl (luster)
Mother rock
Mottled
Multicolored
Multiple oxides (subgroup)
Mylonite