Petroleum jelly is a mixture of hydrocarbons, with a melting point that depends on the exact proportions. The melting point is typically between 40 and 70 °C (105 and 160 °F).It is flammable only when heated to liquid; then the fumes will light, not the liquid itself, It is colorless or has a pale yellow color (when not highly distilled), translucent, and devoid of taste and smell when pure..
Depending on the specific application of petroleum jelly, it may be USP, B.P., or Ph. Eur. grade. This pertains to the processing and handling of the petroleum jelly so it is suitable for medicinal and personal-care applications.