Josiah Wedgwood

In the 1760s Wedgwood improved the body and glaze of Staffordshire cream-coloured earthenware, building on earlier local potters' work. After he supplied Queen Charlotte, the ware was sold as 'Queen's Ware' and he was styled the Queen's potter; it became the staple of his business.

After trials with barium minerals from 1773, Wedgwood had by 1775 developed jasper, a fine unglazed stoneware that could be coloured right through with metal oxides. It was used for cameos, portrait medallions, plaques and vases with white reliefs on blue, green, lilac or black grounds. Church gives an approximate formula in which barium sulphate makes up more than half of the body.

In 1773-74 Wedgwood and his partner Thomas Bentley made a cream-ware dinner service for Empress Catherine II of Russia; according to Williamson it ran to more than 800 pieces, each carrying a green frog emblem and a painted view of a British building or landscape. Before it was shipped, the service was displayed in the firm's new show-rooms in Greek Street, London, in 1774.

In July 1774 Wedgwood wrote to Bentley that his new white body kept coming out differently, sometimes white, sometimes cinnamon-coloured, sometimes melted to glass. Testing each lump of the mineral separately, he found the samples varied, and he turned to a material whose pieces all behaved alike. The account comes from his own letters, printed by Meteyard; the chemist A. H. Church separately describes his difficulty with these minerals.

Isolating one variable at a time, and then choosing a material for its consistency, is consistent with the profile's high analytical rigor score. Analytical Rigour

William Burton, who worked as a chemist at the Wedgwood factory, records that Wedgwood had his throwers weigh each ball of clay against a table of standard weights, had the scraps weighed daily to check waste, and had finished plates weighed in batches. Earlier, from 1759, his experiment books recorded each trial's ingredients by code number and the part of the oven where it was fired.

These routines sit alongside the profile's high detail orientation score; Church, a more critical writer, suggests the same push for exactness made the ornamental wares less lively. Detail Orientation

In 1759, at the end of his partnership with the Fenton potter Thomas Whieldon, Wedgwood leased the small Ivy House works in Burslem for 10 pounds a year and began working on his own account. According to Church, he had kept the right to keep his own improvements secret when the partnership began, and at first he made the models and mixed the clays himself.

Agreeing in advance to keep his discoveries his own offers one example of the forward planning reflected in the profile's planning orientation score, though his savings and the end of the partnership's term also shaped the timing. Planning Orientation