Alter Aeon Online Help

Keywords are:  'minerals felsic mafic karst geothermal hydrothermal saline glacial geology'

When prospecting, you may get a message about a place have a certain
type of geology. These indicate that an area has a greater chance of
finding certain minerals.

The geologic types are:

Felsic     - volcanic type dominated by oxides and silicates. Quartzes,
             obsidians and feldspars like albite and labradorite like
             are abundant. Ores are less common in felsic geology,
             but gemstones such as rutile, zircon and tourmaline
             can be found.

Geothermal - these are areas with dormant volcanoes, often with hot
             springs, geysers or caldera lakes. Sulfur minerals,
             including ores of copper, tin and and sulfate ores of
             zinc, tin, lead, copper, bismuth and silver, dominate.
             Toxic arsenic, antimony and mercury minerals are can be
             found in these places. Gemstones include microcrystalline
             quartzes such as agate, sard, onyx and carnelian.
             
Glacial    - these are landscapes that have been scoured by glaciers.
             There are usually large amounts of ice still present, but it
             can also include landforms such as moraines, eskers and
             post-glacial lakes. Cold-associated minerals are more common,
             while fire-affinity ones are nonexistant. Deposits of pure
             metal nuggets are more common in glacial areas.

Karst      - dominated by carbonate minerals, such as limestone,
             dolomite, marlstone and gympsum. Lower yielding carbonate
             ores such siderite and calamine can be found here. Certain
             carbon sources such as petroleum and graphite are more
             abundant in karst areas, as well fossils. Softer gemstones
             like fluorite, calcite and celestine are most often here.

Mafic      - volcanic type dominated by darker, iron-rich rocks such as
             basalt and olivine. Richers ores of iron, manganese and
             nickel are more common in mafic geology. Gems such as
             peridot and spinel are more likely in mafic regions.

Saline     - the rarest geology, these include salt flats and toxic
             alkaline lakes. Many rare minerals can be found here,
             from various salts to selenium and alabaster to borax
             minerals exceedingly rare ores of copper, tin and silver.

By carefully choosing the geology of where you prospect, you can
increase your odds of successfully finding certain minerals.