ASTM E1968-19,Standard Practice for Microcrystal Testing in Forensic Analysis for Cocaine.ASTM E1968-19 pdf free download.
ASTM E1968-19 describes procedures applicable to the analysis of cocaine using multiple microcrystal tests.
Referenced Documents
ASTM E1459 Guide for Physical Evidence Labeling and Related Documentation;
ASTM E1492 Practice for Receiving, Documenting, Storing, and Retrieving Evidence in a Forensic Science Laboratory;
ASTM E1732 Terminology Relating to Forensic Science;
4. Summary of the Technique
4.1 A small amount of test material containing the suspected
cocaine is dissolved in a dilute acid and th precipitating reagent is added. The crystals that are formed are observed and distinguished utilizing a light microscope.
5. Significance and Use
5.1 This technique involves a chemical-precipitation reaction between cocaine and the precipitating reagent. The habit and the aggregation of the crystals formed could be used to distinguish cocaine from other drugs (6)
5.2 This technique can be utilized on cocaine present in either the salt or free base form.
5.3 This technique does not distinguish between the salt and free base forms.