A large silver-gilt and gold-mounted jewelled pectoral cross on a chain

A large silver-gilt and gold-mounted jewelled pectoral cross on a chain
St. Petersburg, maker's mark 'S.R', marked with essayer's marks for both before 1898, and after 1908
Designed as a series of cabochon rubies with vari-cut diamond detail to the diamond-set cardinal points, attached to a loop formed as a Russian Imperial crown and decorated en suite, marked on reverse of the suspension loop with 56 and 84 standards, and with a maker's mark on a suspension hook; on a later 14k gold chain, designed as a series of alternating deep red cross links and light green squares in translucent guilloché enamel, the reverse of each enamel cross with a double-headed eagle, apparently unmarked
length of cross: 8.9cm (3 1/2in); chain: 32.4cm (12 3/4in).