What ex-mine means on a specimen label
Ex-mine claims a specimen came out of the workings. For species the Handbook records as of post-mine formation, such as chalcanthite, the claim cannot hold.
Ex-mine on a mineral specimen label claims the piece came out of the underground workings rather than off a dump or out of a dealer's stock, usually during production. It is weaker than it sounds: it names no collector and no locality detail, and for a species the Handbook of Mineralogy records as of post-mine formation, such as chalcanthite, described in 1853, the claim cannot mean what it appears to.
In short
- Ex-mine is a claim about where, not when or by whom. It says underground rather than dump or tip. It does not name a collector, does not carry a date, and does not establish a chain of custody the way ex coll. attempts to.
- For some species the phrase is self-contradicting. The Handbook of Mineralogy records chalcanthite as commonly of post-mining formation, and crocoite and langite as possibly so. A crystal that grew after the mine closed did not come out of a working mine.
- The test that works is the closure date. If the mine shut in 1954 and the specimen's other paperwork is from the 1990s, ex-mine is either a claim about old stock or it is wrong, and it is worth asking which.
- Ex-mine is not a synonym for self-collected. Someone else may have taken it out. The two phrases answer different questions and a label that uses one to mean the other is imprecise rather than dishonest.
- It is worth something on ground you cannot get onto. For a mine that is sealed, flooded or long demolished, in-situ material is genuinely distinct from dump material — different associations, better terminations, matrix that is actually the host rock.
| Phrase | Claims | Does not claim | How to test it |
|---|---|---|---|
| Ex-mine | Taken from the underground workings rather than a dump or tip | A date, a collector, that the mine was working at the time | Compare with the mine's closure date and with the species' mode of formation |
| Ex coll. | It was in a named person's collection | That the person collected it, or that the locality is right | Look for the physical label, the number, and the collection's known catalogue |
| Self-collected | The person naming themselves took it from the ground | That they had permission, or that they identified it correctly | It relies entirely on that person's word, which is why the name matters |
| Old stock | It has been in trade a long time | Anything about origin at all | Look at the packaging, the labels underneath, and the style of the number |
| Found 1963 | A date of collection | Who recorded it, or whether the date is first-hand | Check it against the mine's working life and against the label's own age |
The species where ex-mine cannot mean what it says
This is the part that is not in the general provenance discussions, and it comes straight out of the mineralogy.
The Handbook of Mineralogy records chalcanthite as a secondary mineral in the oxidised portions of copper sulphide deposits, commonly of post-mining formation. It grows on timbers, on walls, in the standing water of abandoned workings, out of copper-rich solutions that had nowhere else to go once pumping stopped. Crocoite carries the qualifier may be of post-mine formation. So does langite.
So for those species, ex-mine and during-production are different claims, and the label conflates them. A chalcanthite crust from a famous Cornish or Chilean mine may be a hundred years younger than the ore it grew on, and it is still genuinely ex-mine in the narrow sense of having come out of the workings. It is simply not what the phrase is normally taken to imply, which is material broken from a working face by a miner.
The useful reframing: ex-mine tells you the specimen came from inside, which is a statement about access, not about age. For a sealed or flooded mine that is a meaningful and sometimes valuable thing to know. It is just not the same as a date, and nobody should pay for it as though it were.
What ex-mine is actually worth, and when it is worth nothing
Being honest about this cuts both ways, so here is both directions.
Where it genuinely matters. In-situ material differs from dump material in ways you can see. Terminations are complete because nothing tumbled them down a tip. The matrix is host rock rather than broken spoil. The associated species are the ones that were actually together in the vug, which is information a dump specimen has usually lost. And for a mine that has been sealed for fifty years, in-situ material exists in a fixed quantity that only goes down.
Where it is worth nothing. On a mine that is still accessible, or was accessible recently, ex-mine distinguishes very little — anyone could walk in. On a species that occurs equally well on the dumps. And on a specimen where the physical evidence contradicts it: a rounded, bruised, iron-stained piece with no matrix is dump material whatever the card says.
The general principle our locality page argues applies here too: a provenance claim is worth what it can be checked against. Ex-mine on a piece whose appearance is consistent with it, from a mine whose closure date fits, in a parcel with other paperwork that hangs together, is evidence. The same three words on a bare card are an assertion. Neither is dishonest; they are worth very different amounts.
How to test an ex-mine claim in five minutes
1. Find the closure date. Most historic mines have one and it is usually easy to establish. If the mine closed in 1954 and everything else about the specimen's packaging and lettering says 1990s, the claim is about old stock passing through later hands, not about the collector who wrote the card.
2. Check the species against its own mode of formation. If the Handbook of Mineralogy records it as commonly or possibly post-mine, ex-mine cannot carry its ordinary implication. The species sheets are freely available and this takes a minute.
3. Look at the specimen for dump signatures. Rounded edges, bruised terminations, iron staining in the recesses, no coherent matrix, a fracture surface with weathering on it. Dumps do characteristic damage and it is recognisable — the same evidence our page on telling whether a specimen is repaired teaches you to read.
4. Ask who wrote the label. Not accusingly — just ask. A dealer who knows the parcel's history will tell you, and a dealer who says frankly that it came in a mixed lot and the card was already on it has told you something more useful than a confident answer would have been.
5. Record the answer, not the phrase. On your own catalogue, write what you actually know: locality X; label reads ex-mine; source Y; not independently verified. That is the three-certainty-states approach from our page on labelling and cataloguing, and it means the next owner inherits your evidence rather than your conclusion.
Ex-mine, ex coll. and self-collected: three phrases, three different questions
These get used interchangeably and they are not interchangeable. Each answers a different question and a label may legitimately carry all three.
Ex-mine answers where in the ground. Underground workings rather than the tip. It says nothing about who or when.
Ex coll. answers whose it was. It is a custody claim, and its value depends entirely on whose name follows and whether the physical label and number survive to support it.
Self-collected answers who took it out. It is a first-person claim, so it is only as good as the person making it — and it is the one phrase that becomes worthless the moment the specimen changes hands without the collector's name attached.
A complete provenance would read something like: species and locality, ex-mine, self-collected by a named person on a stated date, then ex coll. so-and-so. In practice you will almost never see all of that, and a label that carries two of the four honestly is better than one that carries all four vaguely.
If you collect by locality rather than by species — which is the British tradition and the more interesting way to do it — then the provenance phrasing is a large part of what you are actually buying, and it is worth being specific about what you want. That is exactly the sort of brief that belongs on a wanted list: a named mine, a named horizon, in-situ material, with whatever paperwork exists. No catalogue is indexed that way, and the material surfaces through people rather than through listings.