Carbon and hydrogen
The measurements of carbon and hydrogen in the Gilsonite are done on very small samples, and therefore the test must be done with sufficient accuracy.
The sample is completely burned in oxygen at 800 degrees Celsius.
The combustion products pass through warm copper oxide and convert all the remaining carbon and hydrogen into CO2 and H2O, respectively. The percentage of carbon in Gilsonite is determined by ASTM-D3172.
The amount of nitrogen in the Gilsonite is measured by the famous Kjeldahl method.
Sulfur has various forms in Gilsonite. The amount of organic sulfur will be obtained from the difference in total weight of sulfur and sulfur minerals. The percentage of sulfur in Gilsonite is determined by ASTM-D1552
The amount of oxygen in the Gilsonite cannot be measured directly by any reliable method.