You should try minimum 6 ratti and above. Definitely you should test it before you wear it.
Good procedure to Test Blue Sapphire
1. Take piece of Cloth and make it like a tube. Put Blue Sapphire stone in it and tie it on your biceps for minimum 1 week. By this way you wear it for 24/ 7 and will know about its genuine effects.
If all goes well you can convert in into a ring and wear it.
Blessings,
Navneet Khanna
Astrologer