Geomancy is a story-based adventure mod, featuring:

• smithing jewelry and socketing gems in them
• uncovering the story of large, ancient ruins buried underneith the worlds mountains
• discovering a unique, otherworldy yet technological spin on spellcasting
• losing ones mind
• lead poisoning

It adds several new ores, such as lead, titanium, mithril and molybdenum, and one strange outlier thats hard to describe.
Don't worry, it'll tell you more itself.
...Maybe it's better if you don't listen, though.