Fort Diamond weathered the Pearl Rock to bear down on a French privateer schooner, Mosambique, which had anchored close to the shore under a battery at Ceron, outside the port of Saint-Pierre, Martinique.

In cooperation with Emerald and Pandour, which sent two boats each to create a diversion, Fort Diamond ran alongside the schooner, running into her at a rate of about nine knots an hour.

At her approach, the schooner's crew fired a broadside and discharged some small arms before all 50 or 60 crewmen jumped overboard and swam ashore.

The impact of Fort Diamond's strike broke the chain that anchored the Mosambique to shore, and the boarding party cut two cables to free her.

That year she was returning from having escorted several vessels to Tortola to join a convoy when she encountered the French privateer Grande Decidé, of 30 guns and 250 men.

[12] On 29 March 1808, Cerberus, in company with Lilly, Pelican, Express, Swinger, and Mosambique, sailed from Marie-Galante to attack the island of La Désirade.

Sherriff, of Lily, the commander of the squadron to which Mosambique belonged, reported that he was particularly pleased at the capture as the Jean Jacques had been sent out for "the express Purpose of cruising in these Seas, and, from her superior Sailing, would have proved a great Annoyance to the Trade."

[15] On 20 December Admiral Alexander Cochrane appointed James Atkins, who had been Acting Master of Grenada, to the rank of Lieutenant and command of Mosambique.

[16] In 1847 the Admiralty authorized the issuance of the Naval General Service Medal with clasp "Martinique" to all surviving claimants from the action.