soils

Alluvial - A combination of clay, silt, sand and gravel that forms over time from mineral deposits left by running water.

Calcareous - A soil primarily composed of calcium carbonate and high in chalk or limestone as well as fossilized shells.

Granite - A hard and granular rock with a high content of crystals, particularly quartz.

Jory - A volcanic soil composed mostly of basalt, which is in turn a hard and dense soil that often has a glassy appearance.

Limestone or Chalk - A soft soil made primarily from fossilized seashells.

Loam - A crumbly mixture of clay, sand and silt.

Marl - A crumbly mixture of different clays as well as calcium and magnesium carbonates with fossilized shells mixed in as well.

Sandstone - A combination of silica and sand compacted together by pressure and time.

Schist - A metamorphic rock derived mostly from clay, but it can be made from several other rocks. Schist is a soft rock that flakes and breaks easily.

Shale - Layers of clay-like, fine-grained sedimentary rock. On the surface where the shale breaks it often forms beds of sharp fragments.

Tufa - A mix of silica, calcium carbonate and sometimes volcanic ash that has been deposited over time by streams, lakes and other water sources.