Where in the earth is aquamarine formed?

Brazil is the largest producer of aquamarines; other important producers are Pakistan, Myanmar (Burma), Russia, China, Namibia, Mozambique, Zambia, Kenya, and the United States (Colorado and California).

Beryl largely comprised of beryllium aluminium cyclosilicate and located in deposits known as granitic pegmatites, which are large structures comprised of interlocking minerals and rocks.

These deposits are sometimes pushed to the surface through natural geological processes. When beryl deposits are forming in the presence of iron it is likely that the crystallization process will result in aquamarine gemstones. As the beryl crystals form iron is essentially trapped inside, fusing with them. If little or no other impurities are present these processes result in aquamarine gems. When other impurities are present the beryl may form into maxixe, emeralds, or golden beryl, amongst others.Source: http://aquamarinenecklacereviews.com/aquamarine-gemstones-formed-geological-processes/

Aquamarine is formed in much of South America including in Brazil. This gemstone is also found in Australia, India, China, Madagascar, and in Zambia.