When to wear Panna stone

As per Hindu Astrology Panna Stone(Emerald Stone) is the Gem of Mercury i.e., The mantra for this Planet is Budh “ Om! Braam Breem Broom Sah Budhai Namah”. This should be chanted 108 times in a single sitting on a onyx mala of 108 beads. 

Panna stone will give effects within 45 days after wearing and till 3 years it will give full effects, after that it becomes inactive, You must change your gemstone after inactivation. 

If we talk about emerald in hindi then we find the name like Panna.