The Royal Asscher Diamond Company () was founded in 1854 by the Asscher family of gemcutters. The company is responsible for cutting some of the most famous diamonds in the world including two of the top three largest diamonds ever found. Its headquarters still stand at its original location Tolstraat 127 in Amsterdam, the Netherlands. The company also has regional headquarters in New York City (Royal Asscher of America) and Tokyo (Royal Asscher of Japan). Royal Asscher is still owned by the Asscher family, today a renowned diamond dynasty. The Asscher Diamond Company, made famous at the turn of the 20th century by Joseph and Abraham Asscher, became Royal Asscher Diamond Company in 1980 when it was bestowed with the Dutch Royal Predicate from Queen Juliana of the Netherlands in recognition of the company's stature both in the Netherlands and across the world. In 2011 Queen Beatrix perpetuated the Royal Prefix for another 25 years. History The establishment of the company In 1854 Joseph Isaac Asscher, a known artisan in the diamond industry, established the I.J Asscher diamond company, named for his son Isaac Joseph Asscher, who followed in his father's footsteps and entered the diamond industry. He passed down his expertise to his five sons, including Joseph (a prolific and unrivalled diamond cleaver) and Abraham (a talented innovator and businessman). Together, they became the 20th century's most prodigious diamond experts. Under Joseph and Abraham, the company was known as the Asscher Diamond Company and cut diamonds to be set in jewellery for world famous boutiques and maisons internationally. As one of the largest diamond polishing companies in the world at that time, the company was known for having royalty, celebrities, and politicians as private clients. The Asscher Cut In 1902 Joseph Asscher designed and patented his namesake original Asscher cut. This emblematic cut was the world's first patented diamond cut, protecting it from replication by other companies. The Asscher Diamond Company held its exclusive patent until the Second World War and saw strong sales internationally, particularly during the 1920s and 30s when the cut and company were both at the height of success. The original design had 58 step-cut facets, a small table, high crown and steep pavilion with cut corners. An accurate description would be a cut cornered square emerald cut diamond. Also known as square emerald cuts, Asscher cut diamonds are roughly square in shape when viewed