Color can vary within one deposit and repeat across unrelated rocks; locality links anatomy to geologic context.
The practical rule
- Formation and locality help determine age and plausible taxa.
- Color may reflect minerals, weathering, polishing, or treatment.
- Good provenance survives beyond the current seller’s memory.
What to record
Preserve the original seller description, photographs, invoice, claimed locality, formation, age, dimensions, and every statement about preparation or restoration. Add your own interpretation as a dated note rather than replacing the original record.
What makes a stronger collection
A coherent collection is not necessarily the largest or most expensive. It contains specimens that can be compared, explained, and traced. Documentation turns a decorative object into a durable teaching and research asset.
Next step
Choose one specimen and improve its record today: photograph the reverse, measure it, transcribe the label, save the invoice, or document restoration boundaries.
Build a comparison set
Repeatable method: use the identification workflow, authenticity guide, legal and ethical guide, and value guide. This page focuses on specimen-specific morphology, locality, preparation, or collecting context.
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