Significant deposits of clay, limestone, marble, silica, and phosphate exist.

Unfortunately, the deposits that could prove such a drainage system existed have not been found.

Extensive deposits exist at Tivoli, near Rome.

Petroleum, natural gas and other similar deposits also exist.

Small deposits of coal, gas, and petroleum exist but have not yet been developed.

A bigger factor, however, is whether such deposits exist outside Borneo.

Although rare, deposits of native chromium exist.

Similar deposits probably existed on Mauna Loa, but have been covered by later lava flows.

Quaternary Period rock, glacial deposits and gravels exist in the Calder Valley.

Large deposits of bituminous coal existed.