Becker V (1987) Antique and Twentieth Century Jewellery. Colchester: NAG Press, 2nd ed. ISBN: 0719801710.
The text discusses the difficulty of continuation of the Arts and Crafts style into the 1920s and 1930s. (Sybil Dunlop pages 240, 288, 19.13)
"This continuation of style can be confusing for collectors: there were silversmiths and jewellers working from about 1915 to 1930 in the Arts and Crafts style, such as Sybil Dunlop and George Hunt. their work is distinctive however; and experience and comparison will eventually help the collector to recognise early and late Crafts revival pieces." pg 240
It is difficult to see clearly with this photograph but the leaf forms and coils are more reminiscent of the work of Dorrie Nossiter than that of Sybil Dunlop whose leaves are more stylised than naturalistic.
19.13 Group of rings showing the use of cabochon, semi-precious stones, and leaf and flower clusters. In the centre ring by Sybil Dunlop, about 1920. Below: Gold and opal ring by Archibald Know. (Bellamy; Editions Graphiques; Gooday;The Purple Shop)