My question revolves around the setting for one of my cities. I decided to place it by the coast but that brings with it some questions. Can I still have farms and fields outside a coastal city? Can a gem mine be close to the sea? I am not very experienced with geological stuff or why certain things can be at site A while others can't be at site B. If someone smarter than me could answer this question I would be grateful.
farms and fields are often found on river deltas so that's no problem - a mine is less likely but you could have diamonds or similar brought down by rivers and found in alluvial grit
Gem mines are wherever there were volcanoes, land or sea. I live in California and frequent the gem mines for trying my luck at some good tourmalines. I also used to live in Duluth, MN, right at the tip of Lake Superior. The city is built on an old volcano. The shoreline is an excellent place to find various nodule and geodes. Gem and crystal mines are everywhere.
The one problem you'd have with a gem mine near the sea is the water table. Not sure exactly how quickly it drops off or how far from the sea your mine is, but if you dig a hole in the dry sand at the beach, eventually you'll hit water. Same thing with a mine, which is why pumps are very important in some places. EDIT: And I see @Necronox beat me to it, but my browser hadn't updated.
Also as EFMingo said above, the real key for gems are volcanoes, either active or ancient. That’s why a lot of scientists think that Olympus Mons on Mars may have gemstones.
Absolutely has gems. Imagine, a volcano three times as high as Everest. The size of the crystals it could hold!
@Cave Troll Yep, a big handful of tourmalines. Their fun to dig for, but a hell of a lot of work. Mines are up the coast or slightly inland.
First I read this as a Germ Mine (haha) They are mostly around volcanoes as other have said, but can also be near the ocean, it really depends. You could do some research and see what kind of mines tend to be where. Find one that exists similar to yours.
You should check out the geography of Cape Breton in Nova Scotia. Place used to have hundreds of coal mines, rolling fields, pastures chock full of sheep, and all on an island in the Atlantic that's about 180 click at the widest.
Of course. Look at the agricultural history of California. Malibu was once part of a very large rancho that had cattle. If you go slightly inland from Oxnard, a sleepy beach town off the Pacific Coast Highway, there's a large agricultural area that is, among other things, the largest strawberry producer in California. Upstate, the Strauss creamery has pastures that overlook the ocean. Hearst ranch (as in William Randolph Heart) still raises cattle and is very close to the ocean. ETA: @EFMingo And now I'm wanting to swap sea glass hunting for digging tourmalines!
