ore
Opal is a valuable mineral that starts with the letter "O." It is known for its unique play of colors and is often used in jewelry.
Osmium is a mineral. It is a chemical element and has the symbol Os.
Orthoclase
Anything.
Tungsten is the mineral most found deposited in the Arizona mohavee area.
Zircon is a mineral that starts with the letter "Z". It is a silicate mineral commonly used in jewelry as a gemstone.
Aluminum is a mineral. It begins with the letter A.
The mineral-rich soil deposited in the Huang He river is called "loess." It is formed from windblown deposits of silt and clay, and is known for its fertility and ability to support agriculture.
Do you mean what Norse god starts with o? Odin is a Norse go that starts with O.
Halite, the mineral deposited from crystalizing sodium chloride is sedimentary.
Emerald
Jade