Jewellery, Watches and Objects of Vertu to include the personal archive of Louis Osman, goldsmith and architect

A diamond set cocktail watch, the signed silvered rectangular dial with black Arabic numerals, jewelled movement, lacking crown, in white precious metal case, the bezel pavé set with single-cut diamonds, with baguette-cut diamond accents, to articulated tapered shoulders, one broken, set with single-cut diamonds, each link centred with a principal collet set old brilliant-cut diamond, to black cordette strap, dial length 12mm. £400-500