Reference collection
Definition
A curated library of verified specimens from known species, subspecies, and geographic populations used as comparators in forensic identification. The depth and taxonomic breadth of a reference collection determines how many identification questions a laboratory can answer.
- Purpose
- Comparison standard for identifying unknown plant material, pollen, or wood in forensic cases
- Common formats
- Microscope slides, herbaria, wood sections, and verified specimens organized by species and region
- Key requirement
- All specimens must be identified with certainty and processed identically to casework samples for accurate comparison
Common questions
What exactly is a reference collection in forensic science?+
A reference collection is a library of identified specimens, pollen slides, or botanical materials that a lab uses to compare against unknown evidence. They're processed using the exact same methods as evidence samples. By matching an unknown sample to a verified specimen in the reference collection, examiners can make reliable identifications.
How does a reference collection help identify evidence at the microscope?+
Examiners place a known specimen slide next to an unknown evidence slide and compare their features side by side under the microscope. This direct comparison is more reliable than trying to identify from memory or a description. The more complete the reference collection, the more types of pollen, plants, and wood the lab can identify.
What kinds of materials go into a forensic reference collection?+
Reference collections typically include herbaria (pressed plant specimens), pollen slide libraries, and wood anatomy reference sets. In wildlife forensics, they contain verified specimens from different species, subspecies, and geographic populations. The diversity and depth of the collection directly determines how many identification questions a lab can answer.
Related terms
- Accreditation body
- An independent national or international organisation that assesses laboratories against ISO 17025 or equivalent standards and grants formal accreditation. Examples include UKAS...
- Acetolysis
- Erdtman's 1934 extraction method. The sample is treated with a 9:1 mixture of acetic anhydride and concentrated sulphuric acid, which dissolves cellulose...
- Assemblage
- The full community of diatom taxa present in a sample. The relative frequencies and absolute counts of species in an assemblage reflect...
- BfN
- Bundesamt für Naturschutz (Federal Agency for Nature Conservation), Germany. Maintains CITES-supporting scientific expertise and species identification services for German customs and enforcement...
- Blank control
- A sample known to contain none of the target material, processed in parallel with real exhibits to detect laboratory contamination. A positive...
- ENFSI
- European Network of Forensic Science Institutes: the voluntary network of national forensic institutes across Europe and neighbouring regions, focused on method harmonisation,...
- Exotic marker
- A known quantity of an introduced pollen type (often Lycopodium clavatum spores from a calibrated tablet) added to a sample before processing....
- ISO 17025
- International standard for the general requirements for the competence of testing and calibration laboratories. Covers management system requirements (document control, internal audits,...
- Method validation
- The process of demonstrating that an analytical method does what it claims: that it correctly identifies the target analyte, at what sensitivity,...
- NFWFL
- National Fish and Wildlife Forensics Laboratory, the USFWS facility in Ashland, Oregon. Operates the US reference collection for wildlife hair, feathers, bone,...
- Pollen sum
- The total number of pollen and spore grains counted on a slide, used as the denominator for calculating the percentage of each...
- Proficiency test (PT)
- An external blind trial in which a laboratory receives samples of known (but concealed) identity and is evaluated on whether its results...
Explained in these topics
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- Quality Assurance, Reference Collections, and AccreditationA curated set of identified botanical specimens, pollen slides, or wood sections used as comparison standards for identifying unknown exhibits. In forensic bot...
- Global Wildlife Forensic LaboratoriesA curated library of verified specimens from known species, subspecies, and geographic populations used as comparators in forensic identification. The depth an...