Ciro, the great British costume jeweller.
 

Ciro Pearls was founded in Britain in 1917 and traded for 3 years purely as a mail order company before it opened its first shop. It grew fast during the 20s and its adverts appear in all the influential women’s fashion magazines of that era, by 1928 it was ready to make a major expansion in the United Kingdom and in  1939  it opened a flagship store in New York on 5th Avenue.
Unfortunately it suffered, as did many costume jewellery firms, when the market for CJ shrank in the 1970s and 80s; and by 1994 its world wide business went into receivership. The majority of the company was sold together, last owned by Merchants T&F, Inc NY (source RCJ ), and appears to have stopped trading in 2002/2003: but the UK based section was acquired by John Shannon and is still trading today under the name Ciro Pearls Ltd.

Perhaps the most important information I have to offer on Ciro is the copies of their mail order catalogues which I have managed to find.

Post World War Two was a time of great austerity in Great Britain and jewellery was low on the list of needs, food rationing did not finish until 1954, so it is hardly surprising that there is little difference between the 1953 catalogue and (what I believe to be) the 1955 catalogue.
What is more surprising is that the 1963 and 1964 catalogues show a strong similarity also. I can only assume that the standard items were presented for mail order purchase and the more ephemeral lines were only available from the shops, certainly they state that the catalogues only carry a selection of their range.
I think that the early catalogues, at least, were produced in the Autumn so that they caught the Christmas trade.

1953 Catalogue ( Coronation year, and date mentioned in text)
1955 Catalogue ( Dated by mention of the film ‘The Prodigal’, released May 1955)
1963 Catalogue ( Date mentioned in text)
1964 Catalogue ( Dated on front)