How to value a mineral collection for insurance
An insurer pays on evidence, not on opinion. The four-document standard sets out what each specimen needs, and which specimens are worth scheduling at all.
An insurer pays on evidence rather than on opinion, so valuing a collection is a documentation exercise before it is a pricing one. Each specimen needs four things: a determination with its certainty stated, a provenance chain, a photograph with the label in the same frame and a scale, and an acquisition record. Review the schedule every 12 months. Specimens without those four are effectively uninsurable whatever a collector or dealer thinks they are worth.
In short
- The four-document standard. Per specimen: species and locality with the certainty stated; the provenance chain; one photograph with the label in the same frame and a scale in it; and the acquisition record. Anything missing one of the four is hard to claim on.
- Photograph the label with the specimen, in one frame. A label photographed separately proves nothing about which specimen it belonged to, and separating the two is exactly what a fire, a flood or a burglary does.
- Unscheduled contents cover has a single-article limit, and a collection is usually assessed against it specimen by specimen rather than as one object. Read that limit before deciding anything else — it determines whether you need a schedule at all.
- Get the opinion from someone who is not also a buyer. This is the same rule as when selling: an offer and a valuation from the same mouth is one number doing two jobs, and it cannot be neutral in both.
- Keep the record somewhere the collection is not. An inventory in the drawer under the cabinet burns with the cabinet. Off-site or cloud, updated when you acquire, is the whole of the discipline.
| Evidence | What it must show | What collectors usually have | How to close the gap |
|---|---|---|---|
| Determination | Species and locality, with certainty stated — analysed, determined, or as-labelled | A species name on an old card | Add a certainty word to each entry; “as labelled” is honest and usable |
| Provenance | The chain of previous owners or collections, as far as it is known | One dealer's label, or nothing | Photograph every old label, including illegible ones |
| Image | The specimen and its label in one frame, with a scale, from more than one angle | A phone photo of the specimen alone | Reshoot with the label alongside and a rule in frame |
| Acquisition | When, from whom, and what was paid | Memory | Retain receipts and invoices; a dated email counts |
| Location | Where the record is kept | In the same room as the collection | Off-site or cloud copy, updated on acquisition |
The four-document standard, specimen by specimen
Insurance valuation is usually discussed as though the hard part were arriving at a number. It is not. The hard part is being able to demonstrate, after the specimen no longer exists, what it was. An insurer settles on evidence, and evidence about a mineral specimen is unusually easy to lose.
1. Determination, with the certainty stated. Not just “fluorite, Weardale” but which of three things that is: analysed, determined by you or by a named person, or simply as labelled by a previous owner. Our note on labelling and cataloguing sets out those states. “As labelled” is not a weakness in a claim, it is a true statement, and a schedule full of true statements survives scrutiny better than one full of confident ones.
2. Provenance. Which collections the specimen has passed through. This is the part that carries real weight in the mineral world and the part least likely to be written down anywhere except the old card itself — which is why photographing every label, including the ones you cannot read, matters more than it looks. Our notes on what ex coll. means and what ex-mine means cover reading those cards.
3. One photograph with the label in the same frame, and a scale in it. See the next section; this is the rule people most often get wrong.
4. The acquisition record. When, from whom, and what was paid. A dated email from a dealer is a record. A memory is not.
Photograph the label with the specimen, in one frame
If you take one thing from this page, take this. A photograph of a specimen and a photograph of its label are two pieces of evidence about nothing in particular. One photograph containing both is evidence about a specimen.
The reasoning is uncomfortable but simple. Labels and specimens get separated — by a move, by a drawer being tipped, by a burglary that takes the specimen and leaves the box, by a flood that takes the paper and leaves the mineral. Every event you are insuring against is an event that separates them. The only moment you can prove they belonged together is now, while they are both in front of you.
The practical version: specimen and label side by side, a rule or scale bar in frame, even lighting, and a second shot from a different angle. Use a rule, not a coin. A coin dates the photograph and is imprecise; a centimetre rule is a measurement. Our note on photographing a specimen honestly covers the lighting, and its argument applies here for a different reason: an insurance photograph that flatters the specimen is worse than useless, because damage present before the loss is exactly what a flattering photograph conceals.
Photograph existing damage and repairs deliberately. A schedule that shows a repaired specimen as repaired is a schedule an insurer can rely on. One that shows it unblemished invites a dispute about what the loss actually was. Our note on spotting repairs covers finding them.
Which specimens are worth scheduling, and which are not
Not every specimen needs to be listed individually, and listing everything is how people abandon the exercise halfway through.
Start by reading your own policy's single-article limit. Ordinary home contents cover pays out on contents up to a total, but usually caps what it will pay for any one item unless that item is specified — scheduled — by name. A collection is normally assessed against that limit specimen by specimen rather than as a single object. That one number decides most of the work: specimens comfortably under it are covered by ordinary contents cover, and specimens over it are not covered properly unless scheduled. The Natural Sciences Collections Association publishes collections-care guidance written for institutional keepers that is useful reading on documentation standards generally.
Then apply the threshold in the other direction — by documentation rather than by value. A specimen worth scheduling but with no provenance, no photograph and no acquisition record is one you cannot substantiate a claim on, so scheduling it achieves less than documenting it would. The order is: document first, schedule second. Reversing those is the commonest mistake.
Three categories fall out of this in practice. Schedule: individually significant pieces, anything with a named old collection behind it, anything you would find genuinely hard to replace. Document but do not schedule: the bulk of a working collection — inventory line, one photograph, locality. Neither: study material, duplicates and unlabelled offcuts, which are a box rather than a set of specimens.
Getting an opinion, and what this site will and will not do
An offer and a valuation from the same person is one number being asked to do two opposite jobs. It is the same rule our note on selling a collection sets out, and it applies with more force here, because with insurance nobody is in the room to argue the other side.
Sources of an opinion that is not also an offer: a university geology or earth-sciences department; a museum curator, who will not value for insurance but will often confirm a determination, which is the harder half; a local or regional mineral society, where the knowledge is concentrated and free; and a professional valuer instructed and paid by you rather than by an insurer.
Be clear which of two figures you are asking for, because they are not the same and people conflate them constantly. Replacement is what it would cost to obtain a comparable specimen today. Indemnity is what the specimen was worth at the moment it was lost, with its age and condition taken into account. A schedule written against one and claimed against the other is a dispute waiting to happen. Ask your insurer which basis the policy uses before you commission anything.
What we do here. This site is a set of reference notes and a wanted list. We do not carry out valuations or appraisals, we do not quote market rates on any page, and we do not hold a catalogue — which is exactly why we are not a suitable source for an insurance figure, and we would rather say so than be asked. What our wanted list does set out is the material and the documentation we look for, and that documentation is the same documentation an insurer wants, for the same reason: it is what makes a specimen identifiable by someone who is not holding it. Our collecting notes cover labelling, provenance and condition in more detail.