Imperial topaz is also known as "precious topaz". It is the most sought after natural Topaz Considered to be the colour of the setting sun, imperial topaz gets its name from the Russian Tsars of the 17th century. This is because the tsars claimed exclusive rights to the pink topaz gemstones that were mined in Russia. Imperial topaz is less common than other types of naturally occurring topaz, which makes it more valuable. Imperial topaz was traditionally considered to be orange with red dichroism, (this means that when tilted in the light, imperial topaz can appear red or orange), but nowadays it is more widely defined as yellow, pink, red, lavender-pink and peach-pink topaz.