Treasure finds during an archaeological evaluation

If a find made during an archaeological evaluation on your land qualifies as treasure, someone has a legal duty to notify the coroner within 14 days, and failing to do so is a criminal offence under section 8 of the Treasure Act 1996. That duty falls on the finder. On a development site the finder is usually the archaeological contractor, but as landowner you are the person whose programme is affected and, in most cases, the person entitled to a share of any reward.

Treasure Act reporting is not the thing that delays sites. Poor contract drafting and unsecured findspots are.

What qualifies as treasure

The Act and the orders made under it define treasure by material, age, quantity and, since 2023, by significance. In outline:

1. Objects other than coins, at least 300 years old, with at least 10 per cent precious metal by weight.
2. Coins at least 300 years old found together, with a hoard threshold that differs according to whether the coins are precious metal or base metal.
3. Two or more prehistoric base metal objects found together.
4. Objects found in association with treasure.
5. Since an amendment made in 2023, certain finds over 200 years old that are of exceptional archaeological, historical or cultural significance, even where they fail the metal test.

Single coins, most pottery, most iron, and post-medieval material outside those categories are not treasure. They are still archaeology, and they are still recorded, but a different process applies to them.

The significance category is the newest and the least intuitive. It exists because the metal-based definitions were excluding objects that mattered, and it means a Roman copper alloy figurine can now be treasure where it would not have been before.

The duty to report and the time limit

Notification goes to the coroner for the area in which the object was found, within 14 days of the find or of the day you first had reason to believe it might be treasure. In practice the report is made through the local Finds Liaison Officer of the Portable Antiquities Scheme, who handles the paperwork and the initial identification.

Two points for a landowner. The duty is on the finder, so it is the archaeologist who reports, and the report should be copied to you. And the 14 days runs from the point of belief, not from the point of certainty, which is why contractors report anything doubtful rather than waiting for specialist identification.

Non-treasure finds are recorded voluntarily through the same scheme. On a professional excavation this happens as part of the normal recording system rather than as a separate exercise.

The coroner's process and what it decides

The coroner determines whether the object is treasure. That determination is now often made on the papers rather than at a hearing, and it is a factual inquiry into the object rather than an inquiry into anyone's conduct.

If the find is declared treasure, it vests in the Crown, subject to prior interests and rights. A museum may then express an interest in acquiring it. If no museum wants it, the object can be disclaimed and returned.

Nothing about this stops the excavation. The object leaves site for identification and the archaeological work continues under the written scheme of investigation, which is normally secured by a condition on the planning permission.

Valuation and rewards

Where a museum wishes to acquire a treasure find, an independent valuation process determines the market value, and a reward equal to that value is paid and shared.

The sharing arrangement is set out in the statutory code of practice. Broadly, the finder and the landowner share, and an occupier with an interest may share as well. The proportions depend on the circumstances and on any agreement between the parties.

One rule surprises developers. Archaeologists who find treasure in the course of professional archaeological work are not eligible for a reward under the code. The reward therefore goes to the landowner, subject to any agreement, and that is worth being aware of before a contract says otherwise.

Where the object is disclaimed and returned rather than acquired, there is no reward and the object is dealt with under the ownership arrangements in the contract.

The contract with the archaeological contractor

This is the part within your control, and the part most often left to a standard template.

A contract that works addresses:

1. Who reports treasure, within what period, and who is copied.
2. Ownership of non-treasure finds, which are normally donated to the receiving museum with the landowner's written agreement.
3. Deposition of the site archive, including any museum charges for accession.
4. Security arrangements and confidentiality over findspots.
5. Whether the contractor asserts any interest in a reward, which under the code they cannot claim.
6. What happens to the programme and the price if the discovery triggers further excavation.

The last point is the commercial one. An evaluation that finds a hoard rarely ends at the evaluation. The county archaeologist may ask for an extended excavation around the findspot, and the cost of that sits outside the original quotation unless the contract provides for it.

Our note on post-excavation assessment, archive and publication covers the downstream obligations that follow, and those are often a larger cost than the fieldwork itself.

Site security and publicity

A findspot that becomes public before the site is cleared attracts illegal metal detecting, which is a real and persistent problem on rural development sites. Unauthorised detecting on a scheduled monument or protected place is an offence under the Ancient Monuments and Archaeological Areas Act 1979, and theft is theft anywhere.

Practical measures: keep the findspot off social media and out of the site newsletter until fieldwork is complete, brief the whole site team rather than just the archaeologists, lock the compound properly at night, and agree with the contractor that any press release is issued jointly and after the fact.

Publicity later is usually welcome. A hoard from your land, properly published, is a genuine planning benefit to point at in a heritage narrative, and it costs nothing to say so in the Heritage Statement for a later phase.

What this means for the development programme

Assume a treasure find costs you weeks rather than months, and that the variable is the archaeological response rather than the coroner.

The realistic risks are an extension of the excavation area, a requirement for specialist conservation of fragile material, and a longer post-excavation programme. The coroner's determination, museum interest and valuation run in parallel with construction and rarely hold anything up.

The way to control that risk is upstream, at assessment stage. A thorough Archaeological Desk-Based Assessment that identifies known findspots, historic environment record entries and previous detecting activity tells you where the risk sits before you buy the land. A properly scoped Archaeological Field Evaluation then tests it. Both are specialist documents, councils expect a suitably qualified author working to published professional standards, and professional review is strongly advised.

Illustrative example: trial trenching on a 4-hectare edge-of-village site produces a small group of Iron Age gold objects in a single trench. The contractor reports to the coroner within days, the objects go for identification, and the county archaeologist requires a 400 square metre open area around the findspot. The excavation adds five weeks and a post-excavation programme. Nothing about the coroner's process is on the critical path.

This is general guidance, not legal advice; check the position with your local planning authority, the coroner's office or a qualified professional before relying on it. PlanScope provides AI-assisted draft reports for planning applications. Reports should be reviewed before submission. We do not guarantee planning approval.

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