Collecting

Handling and storing specimens

Most damage to a collection happens in a drawer, not in the field. What actually threatens specimens, and what to do about it.

Applies to All specimens

Most damage happens in a drawer, not in the field. Store specimens in individual boxes, out of direct sunlight, in stable dry conditions. Cleavage rather than hardness is what breaks them: fluorite at hardness 4 has perfect cleavage in 4 directions and still loses corners. Lead and arsenic species are safe in a cabinet.

In short

  • Individual boxes. Loose specimens in a shared drawer scratch and chip each other.
  • Light fades some species — keep vulnerable material out of direct sunlight.
  • Humidity matters: some sulphates and halides are hygroscopic or degrade in damp.
  • Cleavage, not hardness, is what breaks specimens. Fluorite is hard enough and still chips.
  • Lead and arsenic species are safe in a cabinet — do not grind or dust them, and wash your hands.
What actually threatens a collection
RiskAffectsWhat to do
Mechanical damageEverythingIndividual boxes; never wedge or lever
Cleavage fractureFluorite, calcite, bariteSupport the specimen, not the crystal
Light fadingSome coloured speciesOut of direct sunlight
HumiditySulphates, some halidesStable, dry storage
DustFibrous and acicular speciesDo not brush; use air if anything
Handling residueSoft speciesHandle by matrix, not crystals

Cleavage is the real enemy

Collectors think in hardness, but breakage is usually about cleavage. Fluorite at hardness 4 will scratch a fingernail comfortably and still lose a corner to a knock, because it parts cleanly along octahedral planes.

The practical rule: support the matrix, never the crystal, and never lever a specimen out of a tight box. Most damage happens in the two seconds of getting a piece in or out of storage.

Light, and which species care

Not everything fades, but enough does to make direct sunlight a bad default. Some coloured species lose intensity irreversibly with prolonged exposure.

Display is a trade-off you make knowingly: a cabinet by a window looks better and costs you something over years. If a piece is irreplaceable, keep it out of the light.

Lead and arsenic, in proportion

A great deal of classic British material is lead- or arsenic-bearing — pyromorphite, mendipite, scorodite, olivenite, clinoclase. These are safe in a cabinet and safe to pick up.

The precautions are ordinary and worth taking anyway: do not grind, saw or dust them, do not eat while sorting a collection, wash your hands afterwards, and keep specimens where small children cannot help themselves.

Questions

How should mineral specimens be stored?
In individual boxes rather than loose in a shared drawer, out of direct sunlight, in stable dry conditions.
Why does fluorite chip so easily?
Perfect octahedral cleavage in four directions. Hardness is not the issue — it parts cleanly along those planes under modest force.
Are lead and arsenic minerals dangerous to collect?
Not in a cabinet. Do not grind, saw or dust them, do not eat while handling them, and wash your hands afterwards.