S
 
Saccharoidal
Saline
Saline deposite
Saline lake
Salinity
Salt
Salt dome
Sand
Scalenohedral
Scalenohedron
Scales
Scaly
Scepter
Sclerometer
Schiller
Schist
Secondary
Secondary mineral
Sectile
Selenides (subgroup)
Selvage
Sediment
Sedimentary rock
Sedimentation process
Semi-metal
Semi-metallic
Semi-metallic elements (subgroup)
Semi-precious stone
Series
Setting
Shaft
Sheaflike
Sheet silicates
Shelly (fracture)
Shortwave
Silica
Silicafied
Silica gel
Silica group
Silicates (group)
Sill
Silky (luster)
Silt
Simple oxides (subgroup)
Simple sulfides (subgroup)
Sinter
Sixling
Skeletal
Slab
Slag
Smelt
Smooth (fracture)
Soil
Solid solution
Solidify
Solubility
Soluble
Sorosilicates (subgroup)
Spar
Specific gravity
Specimen
Spectra
Spectral
Spectrograph
Spectrophotometer
Spectroscope
Spectroscopy
Spectrum
Sphenoidal
Spherulite
Spherulitic
Spinel
Splendent (luster)
Splintery (crystal habit)
Splintery (fracture)
Stable
Stalactites
Stalactitic
Stalagmites
Stalagmitic
Staurolite twin
Stellate
Stock
Stone
Streak
Streak plate
Striated
Striations
Strata
Stratification
Stratum
Structural
Structure (minerals)
Structure (rocks)
Stubby
Stud
Subconchoidal (fracture)
Subgroup
Sublimate
Sublimation
Submetallic (luster)
Sulfates (group)
Sulfides (group)
Sulfosalts (subgroup)
Sulfuric acid
Surrounding rock
SW
Swallowtail twin
Syenite
Symmetrical
Symmetry
Synthesized
Synthetic
Synthetic gem