The highlight was this 61/2in (17cm) diameter, 17th century Portuguese mariner’s astrolabe from the San Francisco wreck. It was discovered by one of the diving team hidden deep within a gully which had helped to preserve it in relatively unabraded
condition. The instrument is signed Nicola(o) Rvffo and dated 1645 but its most unusual feature is that the entire piece is silver-plated, a unique feature in the known corpus of mariners’ astrolabes. It sold for £110,000 (plus premium) to the Mariners’ Museum in Virginia.
17th century Portuguese mariner’s astrolabe
USA: A 137-lot collection of marine archaeological artefacts salvaged by the company Arqueonautas from seven wrecks on the reefs of the Cape Verde Islands rounded off Sotheby’s horological and scientific auction on December 19.