Diamond ring, circa 1920. The modern brilliant cut diamond as we know it now was invented by the diamond cutter and engineer Marcel Tolkowsky in 1919, but even before this diamond cutters had gradually developed and refined a general shape for round and cushion-shaped diamonds which laid the foundation for Tolkowsky's innovations. This diamond is a beautiful example of late 19th century diamond cutting, with fewer, larger facets reflecting bright flashes of light and colour, prioritising the stone's transparency and dispersion (splitting white light into rainbows) over sheer brilliance. Diamonds in these older cuts are often recut into modern shapes, meaning that the original cuts are getting rarer and more sought after over time. This example is set as a simple solitaire, giving total focus to its beautiful central stone - nothing else is needed.