From the dependency on ample light required within for the diamond cutting and polishing work to be carried out, the Asscher Diamond Company chose Tolstraat 127, Amsterdam, to set up its factory with the castle-like building's massive windows.

Over time, Asscher Diamond Company grew into one of the largest diamond manufacturers in the world, cutting and polishing diamonds for famous jewelry houses in Europe and the United States. At the turn of the century, over 500 diamond polishers worked in the building alongside numerous administrative staff and Asscher family members. All around the factory, known as Asscher Quarter, were beautiful cottages where many diamond polishers lived. Such was the stature of Tolstraat 127 that the surrounding neighborhood became known as Amsterdam's Diamantbuurt (Diamond District), an area that includes today Cullinanplein (Cullinan Square), Diamantstraat (Diamond Street), Robijnstraat (Ruby Street), Saffierstraat (Sapphire Street), and Smaragdstraat (Emerald Street).

Within this grand building, some of the world's largest and most iconic diamonds were cleaved and polished, including the world's largest-ever gem-quality rough diamond, the Cullinan.

Despite the 2nd World War deeply affecting the Assher family and their company, the glorious events that took place within the walls of Tolstraat 127 had already etched themselves in the annals of history. While the old factory is now a light-filled luxury apartments complex, the main tower remains Royal Asscher's headquarters to this day.

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