We propose using elemental sulfur data to estimate gypsum content, or gypsum equivalent, for some soils. At the Soil Survey Laboratory (SSL), combustion analysis for carbon, nitrogen, and sulfur is routinely performed in the characterization of soils. Elemental sulfur data is readily converted to hypothetical maximum gypsum content. A comparison of converted elemental sulfur data from the SSL archive with associated gypsum data shows strong correlation between the data sets. Mutual bias between the proposed method and the routine SSL method is evaluated in the discussion of conditions under which combustion analysis can be employed to estimate gypsum, or gypsum equivalent.