orexemplet

Orexemplet is a term used in geology and mining education to describe a small, standardized ore specimen prepared for laboratory testing and demonstrations. The word combines ore, indicating the mineral content, with a diminutive suffix to signal its miniature, representative nature. It is used in several university manuals and industry training programs to refer to a compact sample that can be easily handled and tested without processing larger material.

Description and characteristics: Typical orexemplets measure about 1 to 3 centimeters in their longest dimension. They are cut or chipped from a larger ore sample to reflect its modal mineralogy and ore grade, and they are often sealed in clear containers with labels that record ore type, locality, and approximate grade. The specimen commonly includes the principal ore minerals along with a representative amount of gangue to illustrate texture and association.

Preparation and standards: Orexemplets are produced by selecting multiple sub-samples from core, drill, or bulk material, composing a representative composite, and then fabricating a small, standardized piece. Preparation follows standard QA/QC practices to minimize bias, including documentation of provenance and homogenization procedures. They serve as targets for instrument calibration (such as X-ray fluorescence or ICP-MS) and as training aids for sample handling.

Applications and limitations: In education, orexemplets support hands-on learning about ore textures, mineral associations, and basic assay concepts. In industry, they function as reference samples for method validation, proficiency testing, and early-stage quality control. Limitations include deposit heterogeneity—no single tiny sample fully captures variability—so results are interpreted alongside larger samples and multiple specimens.