The boat was originally sold as the Yachting World Keelboat in the hope that it would be adopted as a national and international racing class. After years of being nicknamed the Diamond Class, the design was renamed the Yachting World Diamond; the class name was officially adopted in 1967. Sixty years after its conception, Holt’s design continues to attract devotees.
Design and Construction
The Diamond is a multiple-chine sailing yacht, nominally 30 feet overall, designed for racing and short-range inshore cruising. Sources differ on its beam: one gives 2.10m and another 2.03m.
R&W Clark of East Cowes built the prototype, Zest. The boat was thoroughly tested in the hard winds and seas of autumn and early winter 1960, surpassing the testers’ highest hopes.
Early hulls were built in timber. Plywood examples included Dianna, built in Tasmania in 1961, and Black Diamond, built by Coombes of Bosham in 1962. Around the same time, Bristol Aeroplane Plastics Ltd began moulding GRP yachts and introduced a GRP cruising version in 1962.
From the mid-1970s, Diamonds began to be built in fibreglass, with the resulting lower weights improving performance. GRP foam-sandwich boats appeared in the early 1980s, though they generally only replaced ageing wooden yachts.
Rig, Racing and Handling
R&W Clark tested two rigs on the Diamond—a masthead rig and a three-quarter fractional rig—before the testers settled on a compromise: a 7/8ths fractional rig. The original designs called for three or four sails, and the boat could be raced with a small crew. The prototype Zest carried the identification number 1 on her sail beneath a black diamond.
The first GRP Diamond, Bristol I, was helmed by Jack Knights to overall victory in the Round the Island Race that July. In the mid-1970s, Port Phillip sailors began experimenting with twin trapezes to cope with the area’s typically windy conditions. It wasn’t long before trapezes were officially adopted nationwide.
Accommodation and Cruising Conversions
The original design provided two sleeping berths forward, with the possibility of using two inflatable mattresses aft on overnight trips, along with rudimentary domestic facilities. The fairly prominent camber of the foredeck created sitting room forward.
The GRP cruising version had a cabin top covering two berths, plus two more berths beneath the raised aft deck. Later cruising conversions expanded the accommodation considerably. Dianna was converted with a four-berth cabin, an outboard well, a centreboard and a transom-hung rudder. During her 1985 conversion for ocean racing, Saltash II received a cabin and self-draining cockpit.
Refits and Individual Boat Histories
The histories of individual Diamonds show how extensively the design has been modified. According to an owner report, the cockpit of Eclipse, a 1963 plywood boat, was altered to resemble that of an Etchells. A spinnaker chute was also fitted, and hull weight was reduced by 80kg.
Bristol I, the 1961 race winner, was converted into a cruising yacht with a cabin and diesel engine before falling into disrepair. Dartmouth sailors Peter Boote and Kit Noble bought her in 2012 and restored her to her original configuration. After Noble sailed a Diamond in Australia, they also added two trapezes.
Dianna later had her cabin extended and a teak deck laid. Her spars were painted gold anodised, an electric winch was added for the centreboard, and a new cassette-mounted rudder was fitted farther forward.
The most accomplished example, the 1966 plywood boat Saltash II, was converted for ocean racing in 1985. The work included more robust bow frames, a cabin, a self-draining cockpit and an inboard engine. She is currently being restored by the Wrights, who are replacing all her hull skins with new plywood and incorporating epoxy coatings and a lightweight carbon weave.
The Verdict
The Yachting World Diamond is a Jack Holt design that has proved remarkably adaptable over six decades, from the planked prototype Zest to foam-sandwich cruisers and trapeze-equipped racers. Its 7/8ths fractional rig and multiple-chine hull produced a boat competitive enough for the first GRP example to win the Round the Island Race. In Australia, the fleet went on to push the class into twin-trapeze sailing and offshore racing.
Relatively few timber examples survive, but the class is enjoying renewed interest, with weekly racing in Victoria.
Pros
- Jack Holt design with a continuing following 60 years on
- Proven racing pedigree, from the prototype trials to an overall Round the Island Race win
- Adaptable to trapeze racing, cruising conversions and foam-sandwich construction
- Active class association and weekly racing in Australia
Cons
- Relatively few of the 130 timber versions are believed to survive
- Rudimentary original accommodation, with only forward berths and aft mattresses
