Abstract
Sulphur deposits occur in the formation or volcanics of various geological ages.We can in general classify genetically into two types. One is related with volcanic actions and the other is not related.
In Japan, all the deposits belong to the former. after the tertiary to the recent. The sulphur deposits are classified into the following by a different origin.
1) Sublimation deposit
2) Molten sulphur deposit a) Old b) Recent
3) Volcanic sedimentary deposit.
a) Sedimentary molten sulphur.
b) Sedimentary muddy bed. 1. Old 2. Recent c) Sediments in solfataric springs.
4) Impregnation-replacement deposit.
a) Old b) Recent c) Artificial
5) Composite deposit of sedimentary-impregnation -replacement.
In foreign, there are many deposits not related with volcanic actions. Some examples are the sulphur ore beds in Sicily Island, Italy, and the sulphur deposits associated to the salt dome in Louisiana, Texas etc. U. S. A.
The writer described the occurrences of each type.
Sulphur ores are used as materials of refined sulphur and in addition to this as materials to make sulphuric acid with iron sulphide ores-pyrite, marcasite and pyrrhotite. He stated the present internal and external affairs of supply and demand. Besides he expressed his opinions to forecast the future with statistical data.
