ASTM C 25:2024

1.1 These test methods cover the chemical analysis of high-calcium and dolomitic limestone, quicklime, and hydrated lime. These test methods are classified as either standard (preferred) or alternative (optional). 1.2 The standard test methods are those that employ classical gravimetric or volumetric analytical procedures and are typically those required for referee analyses where chemical specification requirements are an essential part of contractual agreement between buyer and seller. 1.3 Alternative or optional test methods are provided for those who wish to use procedures shorter or more convenient than the standard methods for the routine determinations of certain constituents. Optional test methods may sometimes be preferred to the standard test methods, but frequently the use of modern and expensive instrumentation is indicated which may not be accessible to everyone. Therefore, the use of these test methods must be left to the discretion of each laboratory. 1.4 The analytical procedures appear in the following order: Section Aluminum Oxide 15 Available Lime Index 28 Calcium and Magnesium Oxide: Alternative EDTA Titration Method 31 Calcium Carbonate Equivalent 33 Calcium Oxide: Gravimetric Method 16 Volumetric Method 17 Carbon Dioxide by Standard Method 22 Combined Oxides of Iron and Aluminum 12 Ferrous Iron Appendix X5 Free Calcium Oxide Appendix X6 Free Moisture in Hydrated Lime 21 Free Moisture in Limestone 20 Free Silica 29 Insoluble Matter Including Silicon Dioxide: Standard Method 8 Optional Perchloric Acid Method 9 Insoluble Matter Other Than Silicon Dioxide 11 Loss on Ignition 19 Magnesium Oxide 18 Manganese: Bismuthate Method Appendix X4 Periodate (Photometric) Method 27 pH Determination of Alkaline Earth Solutions 34 Phosphorus: Titrimetric Method Appendix X3 Molybdovanadate Method 26 Silicon Dioxide 10 Strontium Oxide Appendix X2 Sulfur Trioxide 23 Total Carbon: Direct Combustion-Thermal Conductivity Cell Method 32 Total Carbon and Sulfur: Combustion/Infrared Detection Method 35 Total Iron: Standard Method, Potassium Dichromate Titration 13 Potassium Permanganate Titration Method Appendix X1 Ortho-Phenanthroline, Photometric Method 14 Total Sulfur: Sodium Carbonate Fusion 24 Combustion-Iodate Titration Method 25 Unhydrated Oxides 30 1.5 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. For specific precautionary statements, see 9.3 , 10.2.1 , 18.4.3 , 31.6.4.2 , X2.3.1 , and X5.4.1.1 . 1.6 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

91.100.10