ASTM D5671-20

Standard Practice for Polishing and Etching Coal Samples for Microscopical Analysis by Reflected Light

SIGNIFICANCE AND USE
5.1 Components observable in surfaces of coal samples prepared in accordance with the laboratory procedures of this practice will have differential relief that will aid in their maceral identification by visual classification and enables identification of plant parts or tissues that formed the coal.  
5.2 Samples prepared by this practice can be used for microscopical determination of the volume percent of physical components of coal in accordance with Test Method D2799.  
5.3 Samples prepared by this practice can be used for the microscopical identification of botanical components by taphonomic rank. Samples for this purpose should be limited to telovitrinite and semifusinite rich coals of bright lithotype to maximize feedback from etching.
SCOPE
1.1 This practice covers laboratory procedures for preparing an etched, polished surface of granular and block samples of coal for examination with a microscope using reflected light illumination.  
1.2 Units—The values stated in SI units are to be regarded as standard. The values given in parentheses after SI units are provided for information only and are not considered standard.  
1.3 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.  
1.4 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.

General Information

• Status: Published
• Publication Date: 30-Sep-2020
• ICS: 73.040 - Coals
• Technical Committee: D05 - Coal and Coke
• Drafting Committee: D05.28 - Petrographic Analysis of Coal and Coke

Standards Content (Sample)

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.
Designation:D5671 −20
Standard Practice for
Polishing and Etching Coal Samples for Microscopical
1
Analysis by Reflected Light
This standard is issued under the fixed designation D5671; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 This practice covers laboratory procedures for preparing 3.1 Terminology used in this standard can be found in
an etched, polished surface of granular and block samples of Terminology D121.
coal for examination with a microscope using reflected light
4. Summary of Practice
illumination.
4.1 Asubsplit of a representative sample obtained in accor-
1.2 Units—The values stated in SI units are to be regarded
dance with Practice D4596 and prepared in accordance with
as standard. The values given in parentheses after SI units are
Practice D2797, or a block of coal obtained in accordance with
provided for information only and are not considered standard.
Practice D5192, is polished to a flat, scratch-free surface; the
1.3 This standard does not purport to address all of the
reflectance of vitrinite is determined on a subsplit in accor-
safety concerns, if any, associated with its use. It is the
dance with Test Method D2798; and then other subsplits are
responsibility of the user of this standard to establish appro-
chemically etched using an acidified potassium permanganate
priate safety, health, and environmental practices and deter-
solution.
mine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accor-
5. Significance and Use
dance with internationally recognized principles on standard-
5.1 Components observable in surfaces of coal samples
ization established in the Decision on Principles for the
prepared in accordance with the laboratory procedures of this
Development of International Standards, Guides and Recom-
practice will have differential relief that will aid in their
mendations issued by the World Trade Organization Technical
maceral identification by visual classification and enables
Barriers to Trade (TBT) Committee.
identification of plant parts or tissues that formed the coal.
2. Referenced Documents
5.2 Samples prepared by this practice can be used for
2 microscopical determination of the volume percent of physical
2.1 ASTM Standards:
components of coal in accordance with Test Method D2799.
D121 Terminology of Coal and Coke
D2797 Practice for Preparing Coal Samples for Microscopi- 5.3 Samples prepared by this practice can be used for the
cal Analysis by Reflected Light microscopicalidentificationofbotanicalcomponentsbytapho-
D2798 Test Method for Microscopical Determination of the nomic rank. Samples for this purpose should be limited to
Vitrinite Reflectance of Coal telovitrinite and semifusinite rich coals of bright lithotype to
D2799 Test Method for Microscopical Determination of the maximize feedback from etching.
Maceral Composition of Coal
6. Apparatus
D4596 Practice for Collection of Channel Samples of Coal
in a Mine
6.1 Ultrasonic Cleaner, large enough for sample holder and
D5192 Practice for Collection of Coal Samples from Core sample preparations to be immersed in cleaning solution.
6.2 Beakers—Glass beakers of (50, 100, and 500) ml
capacity, one each for each etching setup.
1
This practice is under the jurisdiction of ASTM Committee D05 on Coal and
Coke and is the direct responsibility of Subcommittee D05.28 on Petrographic
6.3 Stirring Rods, glass, approximately 20 cm long.
Analysis of Coal and Coke.
Current edition approved Oct. 1, 2020. Published November 2020. Originally 6.4 Hot Plate, electric or gas-heated with capability for
approved in 1995. Last previous edition approved in 2019 as D5671 – 95(2019).
temperature control and rotating stirring magnets.
DOI: 10.1520/D5671-20.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or 6.5 Watch Glasses, glass, 100 mm to 200 mm in diameter,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
depending on size of specimen blocks to be etched.
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. 6.6 Graduated Cylinders, glass, (25 and 100) ml.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D5671−20
TABLE 1 Suggested Plans for Grinding and Polishing of Briquets
6.7 Gr
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: D5671 − 95 (Reapproved 2019) D5671 − 20
Standard Practice for
Polishing and Etching Coal Samples for Microscopical
1
Analysis by Reflected Light
This standard is issued under the fixed designation D5671; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope
1.1 This practice covers laboratory procedures for preparing an etched, polished surface of granular and block samples of coal for
examination with a microscope using reflected light illumination.
1.2 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this The
values given in parentheses after SI units are provided for information only and are not considered standard.
1.3 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.
1.4 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
2
2.1 ASTM Standards:
D121 Terminology of Coal and Coke
D2797 Practice for Preparing Coal Samples for Microscopical Analysis by Reflected Light
D2798 Test Method for Microscopical Determination of the Vitrinite Reflectance of Coal
D2799 Test Method for Microscopical Determination of the Maceral Composition of Coal
D4596 Practice for Collection of Channel Samples of Coal in a Mine
D5192 Practice for Collection of Coal Samples from Core
3. Terminology
3.1 Terminology used in this standard can be found in Terminology D121.
4. Summary of Practice
4.1 A subsplit of a representative sample obtained in accordance with Practice D4596 and prepared in accordance with Practice
1
This practice is under the jurisdiction of ASTM Committee D05 on Coal and Coke and is the direct responsibility of Subcommittee D05.28 on Petrographic Analysis
of Coal and Coke.
Current edition approved Nov. 1, 2019Oct. 1, 2020. Published November 2019November 2020. Originally approved in 1995. Last previous edition approved in 20112019
as D5671 – 95(2011). – 95(2019). DOI: 10.1520/D5671-95R19.10.1520/D5671-20.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D5671 − 20
D2797, or a block of coal obtained in accordance with Practice D5192, is polished to a flat, scratch-free surface,surface; the
reflectance of vitrinite is determined on a subsplit in accordance with Test Method D2798,; and then other subsplits are chemically
etched using an acidified potassium permanganate solution.
5. Significance and Use
5.1 Components observable in surfaces of coal samples prepared in accordance with the laboratory procedures of this practice will
have differential relief that will aid in their maceral identification by visual classification and enables identification of plant parts
or tissues that formed the coal.
5.2 Samples prepared by this practice can be used for microscopical determination of the volume percent of physical components
of coal in accordance with Test Method D2799.
5.3 Samples prepared by this practice can be used for the microscopical identification of botanical components by taphonomic
rank. Samples for this purpose should be limited to telovitrinite and semifusinite rich coals of bright lithotype to maximize
feedback from etching.
6. Apparatus
6.1 Ultrasonic Cleaner—Cleaner, large enough for sample holder and sample preparations to be immersed in cleaning solution.
6.2 Beakers—glass beakers, 50, Glass beakers of (50, 100, and 500 ml 500) ml capacity, one each for each etching setup.
6.3 Stirring Rods—Rods, glass, approximately 20 cm long.
6.4 Hot Plate—Plate, electric
...