Rare Plate, Isleworth, soft paste porcelain, c.1765
This scallop-edged dessert plate is painted in underglaze blue in Meissen 'botanical' style with a central spray and border sprigs alternating with fancy, winged insects.
This plate has a number of characteristics typical of Isleworth porcelain, including horizontal crazing to the glaze, a virtually opaque body, and a dark, almost ‘sunken’ blue.
Provenance: With Stockspring Antiques, London; Private Collection, London.
Both the glaze and underglaze cobalt blue pigment of this piece have been tested using X-Ray Fluorescence Spectroscopy (XRF). The results, published in the English Ceramic Circle Transactions, vol. 28, 2017, reveal that the cobalt blue contains nickel. This is significant as 10 out of 10 of all confirmed Isleworth pieces contain nickel, as do all 36 of the possible Isleworth pieces tested. Compare this with the results for Bow, where no nickel is present in the cobalt blue pigment.
Condition: There are several flat chips to the rim, with associated discoloration. Some of the crazing is also slightly discoloured, and there is general wear to the dull muddy grey glaze from use. Two stilt marks can be seen on the underside. No cracks or restoration.
Dimensions: Diameter 18.5 cm
Transactions, vol. 28 (English Ceramic Circle, 2017). See the entry for item no. 2015-04 123, page 25.
Isleworth Pottery and Porcelain: recent discoveries (English Ceramic Circle and Museum of London, 2003).
Godden's Guide to Blue and White Porcelain, Geoffrey A. Godden (Antique Collectors' Club, 2004).
Bow Porcelain, Elizabeth Adams & David Redstone (Faber and Faber, 1981).
Ref. Adams and Redstone discuss a large octagonal plate painted with this pattern, and with the same characteristics, a piece which they presume to be Bow of the period 1770-74. See Bow Porcelain, pp.172-175, plate 104.
A plate painted with this pattern is also illustrated in Isleworth Pottery and Porcelain: recent discoveries, page 109, where it is mistakenly described as printed.
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