• The Explorer can look for minerals in tiles where you see an eye cursor.
• If any tiles adjacent to your capital city contain minerals, they are already explored and developed.
• Look at the help text at the top right of the screen to see the name of the type of terrain under the cursor. 
• Info-click on a space (right click, or shift click) for a more complete description of everything in the space.
• For more help, click on the question mark button.