CIRO Jewelry began as a mail order company in London, England in 1917. Their ads and order forms were printed in daily newspapers. In 1920 CIRO opened its first store in Bond Street, London. In the 1920s they became especially known for their cultured pearls. Real pearls were expensive and fake pearls before the 1920s were wax or glass and not very convincing, but cultured pearls were good facsimiles of the real thing and CIRO lead the way in their popularity. Fifty years later CIRO also lead the way in popularizing zircons as realistic diamond substitutes. The company is still in business.