If you are an ASTM Compass Subscriber and this document is part of your subscription, you can access it for free at ASTM Compass
    ASTM C25 - 19

    Standard Test Methods for Chemical Analysis of Limestone, Quicklime, and Hydrated Lime

    Active Standard ASTM C25 | Developed by Subcommittee: C07.05

    Book of Standards Volume: 04.01

      Format Pages Price  
    PDF 40 $78.00   ADD TO CART
    Hardcopy (shipping and handling) 40 $78.00   ADD TO CART
    Standard + Redline PDF Bundle 80 $92.00   ADD TO CART

    Historical Version(s) - view previous versions of standard

    Work Item(s) - proposed revisions of this standard

    Translated Version(s): Russian

    ASTM License Agreement

    Shipping & Handling

    More C07.05 Standards Related Products Standard References

    Significance and Use

    4.1 These test methods provide accurate and reliable analytical procedures to determine the chemical constituents of limestone, quicklime, and hydrated lime (see Note 1). The percentages of specific constituents which determine a material's quality or fitness for use are of significance depending upon the purpose or end use of the material. Results obtained may be used in relation to specification requirements.

    4.2 Because quicklime and hydrated lime quickly absorb water and carbon dioxide from the air, precision and bias are extremely dependent upon precautions taken during sample preparation and analysis to minimize excessive exposure to ambient conditions.

    Note 1: These test methods can be applied to other calcareous materials if provisions are made to compensate for known interferences.

    1. Scope

    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:



         Aluminum Oxide 


         Available Lime Index 


         Calcium and Magnesium Oxide:

          Alternative EDTA Titration Method 


         Calcium Carbonate Equivalent 


         Calcium Oxide:

          Gravimetric Method 


          Volumetric Method 


         Carbon Dioxide by Standard Method 


         Combined Oxides of Iron and Aluminum 


         Ferrous Iron 

    Appendix X5

         Free Calcium Oxide 

    Appendix X6

         Free Moisture in Hydrated Lime 


         Free Moisture in Limestone 


         Free Silica 


         Insoluble Matter Including Silicon Dioxide:

          Standard Method 


          Optional Perchloric Acid Method 


         Insoluble Matter Other Than Silicon Dioxide 


         Loss on Ignition 


         Magnesium Oxide 



          Bismuthate Method 

    Appendix X4

          Periodate (Photometric) Method 


         pH Determination of Alkaline Earth Solutions 



          Titrimetric Method 

    Appendix X3

          Molybdovanadate Method 


         Silicon Dioxide 


         Strontium Oxide 

    Appendix X2

         Sulfur Trioxide 


         Total Carbon:

          Direct Combustion-Thermal Conductivity Cell


         Total Carbon and Sulfur:

          Combustion/Infrared Detection Method 


         Total Iron:

          Standard Method, Potassium Dichromate


          Potassium Permanganate Titration Method 

    Appendix X1

          Ortho-Phenanthroline, Photometric Method 


         Total Sulfur:

          Sodium Carbonate Fusion 


          Combustion-Iodate Titration Method 


          Unhydrated Oxides 


    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,, 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.

    2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

    ASTM Standards

    C50/C50M Practice for Sampling, Sample Preparation, Packaging, and Marking of Lime and Limestone Products

    C51 Terminology Relating to Lime and Limestone (as used by the Industry)

    C911 Specification for Quicklime, Hydrated Lime, and Limestone for Selected Chemical and Industrial Uses

    D1193 Specification for Reagent Water

    E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

    E50 Practices for Apparatus, Reagents, and Safety Considerations for Chemical Analysis of Metals, Ores, and Related Materials

    E70 Test Method for pH of Aqueous Solutions With the Glass Electrode

    E173 Practice for Conducting Interlaboratory Studies of Methods for Chemical Analysis of Metals

    E177 Practice for Use of the Terms Precision and Bias in ASTM Test Methods

    E200 Practice for Preparation, Standardization, and Storage of Standard and Reagent Solutions for Chemical Analysis

    E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

    E832 Specification for Laboratory Filter Papers

    ICS Code

    ICS Number Code 91.100.10 (Cement. Gypsum. Lime. Mortar)

    UNSPSC Code

    UNSPSC Code 11111608(Limestone); 30111604(Hydrated lime)

    Referencing This Standard
    Link Here
    Link to Active (This link will always route to the current Active version of the standard.)

    DOI: 10.1520/C0025-19

    Citation Format

    ASTM C25-19, Standard Test Methods for Chemical Analysis of Limestone, Quicklime, and Hydrated Lime, ASTM International, West Conshohocken, PA, 2019, www.astm.org

    Back to Top