Imperial Topaz is in the yellow-orange or reddish-orange (sherry) colour range and has been known since ancient Egypt and Roman times.
The name "Imperial" was given to Topaz in honour of the Emperor Don Pedro of Brazil in order to distinguish it from the heat treated amethyst-turned-citrine known as "golden topaz".
The true Topaz colour is natural and not heated or treated in any way and priced way above that of citrine. When viewed under incandescent light, the orange colour of an Imperial topaz takes on a pinkish hue.
Because of the value, the gem cutters will try to minimize the weight loss as they bring out the natural beauty but this also means that most crystals are a non-standard shape, leading to handcrafted settings instead of mass produced jewellery. The piece of loveliness above is a 7.81 carat stone surrounded by fourteen diamonds in a platinum setting. (drool, want, drool)