Mounting, and why loose is wrong

What loose does

Every time a jar is lifted, carried or set down, the specimen moves against the wall and against anything else in there. Over years that rounds edges, polishes surfaces and removes exactly the detail that makes a fossil worth keeping.

It is worst for the delicate ones

A crinoid, a fossil leaf and a thin trilobite are fragile in ways a tooth is not. For those the mount is not a presentation choice, it is the conservation measure.

Mounted on card, or held in place

A specimen seated in a recess, on a card, or in inert padding so it cannot shift. The padding has to be chemically inert, because something that off-gases is a slow problem in a sealed jar.

Which argues for a jar sized to the specimen

Rather than a large jar part filled. The range here runs 50 to 500 mL across 139 containers, so matching the jar to the object is actually possible on this shelf.

Two specimens in one jar is a mistake

They abrade each other faster than either abrades the wall, and the provenance records get separated the first time somebody sorts them. One specimen, one jar, one card.

Handling is the other half

A fossil taken out and passed around is at more risk than one in a cupboard. For a teaching or display collection, deciding which specimens are handled and which are only looked at is worth doing deliberately.

And the card goes in the mount

Species or group, locality, date, collector and acquisition. Attached to the mount rather than loose in the jar, so it cannot be lost or swapped when a specimen is examined.

It is the cheapest intervention available

A card, a recess and some inert padding cost almost nothing against the value of a good specimen, and they remove the only failure on these pages that happens quickly. Most collections do it for the best pieces and not for the rest, which is backwards for the fragile ones.

References