1.1 ,This test method covers the determination of carbonate content of soils and soft rock which can be readily broken down by mechanical effort. It is a gasometric method that uses a simple portable apparatus. Results should be clearly stated as the calcite equivalent in percent because different carbonate species cover a wide range of percent calcite equivalent as shown below for a number of carbonates:
| Species | Cation | Calcite |
| Magnesite | Mg | 117.0 |
| Dolomite | Ca, Mg | 108.6 |
| Calcite | Ca | 100.0 |
| Aragonite | Ca | 100.0 |
| Rhodocrosite | Mn | 87.1 |
| Siderite | Fe | 86.4 |
| Smithsonite | Zn | 79.8 |
| Witherite | Ba | 50.7 |
| Cerrusite | Pb | 37.5 |