Per Fabrica Ad Astra Mod FAQ

It is a geology and industrial realism mod that overhauls world generation, rock mechanics, and ore progression. Its broader aim is to enhance the technical complexity and realism of Minecraft, eventually extending gameplay to worlds beyond Earth.

Geologica adds realistic geology to Minecraft, defining new types of rocks and minerals. It adds 23 types of rock, 35 types of metal ore, and 25 types of industrial mineral.

It is available for Minecraft 1.6.4, 1.7.2, and 1.7.10.

Yes, vanilla stone is completely replaced by the new types of rocks. Each rock type has corresponding stone, cobble, brick, slab, and wall blocks.

Geologica relies on the Custom Ore Generator mod (CustomOreGen/COG) to place its rocks and minerals in the world. Every aspect of its generation can be overridden using standard COG mechanisms.

Mineral deposits, including metal ores and industrial minerals, spawn in pseudo-realistic veins and clouds according to the type of rock and often the biome. Deposits can appear in stone, sand, or clay form.

The wiki lists two craftable things: a Reference and a Guide.

Yes, cobble blocks may be smelted to stone. Existing stone, cobble, and brick recipes are automatically ore-dictified to support the new rock types.

Deposits include placer deposits of mineral-rich sands on river banks and beaches, banded iron ore, clay limonite, chalcopyrite and gold veins, large coal beds, layered evaporites like rock salt and gypsum, and pegmatite veins.

Its broader aim is to help realize the potential of Minecraft in STEM education, with many ideas directly inspired by nature and actual science. Gameplay takes precedence over realism because if no one plays, no one learns.