ASTM D367 Standard Test Method for Xylene-Insoluble Matter in Creosote
3. Summary of Test Method
3.1 The sample is digested in hot xylene and filtered. The insoluble matter is washed, dried, and weighed.

4. Significance and Use
4.1 The test is useful in evaluating and characterizing creosote and as one element in establishing the uniformity of shipments and sources of supply.