Sluice Box - Boxes or troughs through which gold-bearing gravel is washed. It was the most commonly used tool in mining other than the pan and shovel.

Sluice Claims - A claim worked with sluices.

Smelting - Reducing the ores in furnaces to metals.

Soft Carbonate - Silver-bearing mineral so soft that it can be readily taken out with a pick and shovel. It is usually sand impregnated with mineral, the mineral having been carbonated or oxydized.
 

Sourdough - A highly experienced miner who has prospected for many years.

Square Set - A set of timbers used for support in underground mining.

Stamp or Stamp Mill - Machines for crushing ores.

Stope - A step-like excavation formed by the removal of ore from around a mine shaft.

Stoping - The act of breaking down a stope and excavating it with a pick.

Strata - A series of beds of rock.

Stull - Platforms of timbers between levels for strengthening the mine by supporting the walls, and for storing ore and depositing wall rock and waste material.

Stull Timbers - The large timbers placed across the vein or lode from one wall to another, to support the lagging upon which the ore or waste is placed.

Strike - A find; a valuable mineral development made in an unexpected manner.

Sulphuret - Combination of sulphur with a metallic, earthy or alkaline base.

Sump or Sumph - A pit sunk at the bottom of a mine to collect the water. It can be the bottom of a shaft.

Miners' prospecting, Frederick Remington

Tailings - Gravel, dirt, and rocks that is left behind after extracting the minerals.

Tunnel - A level, driven at right angles to the targeted vein of mineral.

Tunnel Claims - Gold bearing earth taken out of tunnels and subsequently washed.

Vein - Aggregations of mineral matter in fissures of rocks.

Walls - The sides next to the lode.

Wash - The first geological formation, being composed of earth, sand, gravel, and other mineral "washed" down from the mountains during a long series of ages.