Ranging from Neolithic and Roman relics to more recent candlesticks and remnants of modern ordnance, the finds have been recorded mainly by scuba-divers.

The MAS is an initiative designed to improve knowledge of underwater heritage and protect it by encouraging the voluntary recording of items found in English and Welsh waters.

Launched in July 2016, it is funded by the Crown Estate, managed by Wessex Archaeology and modelled on the British Museum’s Portable Antiquities Scheme.

Finders report online or through an app that provides feedback and includes guidance on reporting finds to the Receiver of Wreck. Archaeological experts then research the submitted item’s origins and history, with their findings eventually published on the publicly accessible MAS database.

Only 13 records have been published to date, although this is set to double shortly, the Crown Estate told Divernet, with the rate of reporting expected to increase over time, mainly during the diving season.

"To date, the majority of the finds have come from Kent and Essex, reflecting the especially active diving communities in those areas,” says the Crown Estate.

Divers who possess “legacy finds” – items recovered and reported in previous years – are also invited to submit them to the MAS database.

One example was an almost-complete salt-glazed stoneware barrel costrel, or flask, probably German and 17th century. This was originally recovered more than 50 years ago on a Channel Islands dive to around 18m that also revealed cannon, cannonballs and lead sheeting.

Other finds reported have included onion bottles dating to around 1700, square gin-bottles and 19th and 20th-century pottery.

Unusual items have included remnants of a ship's funnel or ventilator that was to be used in an art exhibition, and a 19th-century surgeon's pestle.

The MAS app for iOS and Android phones and tablets can be downloaded from app stores, or submissions can be made online at marinefinds.org.uk

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