Brown topaz is a variety of topaz found in Pakistan, near the town of Katlang in Mardan district. This mineral has a brownish or reddish-brown colour due to the presence of traces of chromium (Cr3+) in its chemical structure. Brown topaz is a gemstone that boosts self-confidence and removes doubts. It is said to be destined for those who distrust the Universe. Brown topaz is formed in calcite veins in a recrystallized limestone hill, along with other varieties of topaz, such as colourless, grey, yellow, green or pink. Brown topaz crystals can be up to 3 cm long and have a hardness of 8 on the Mohs scale.