i’ve about 4 diamonds rings, and i bought them from differents countries. 1 ring with 3 stones of diamond from Cambodia, 1 ring with 3 stones from Thailand and the other 2 rings from Africa. so my problem is the diamond rings i bought from Cambodia and the sixe is 5.1cm not really shinning i mean after 2 or 3days after clean! and the other 1 i bought from Thailand the size is 3.5cm always keep shinning all the time. so can you guy tell me how to clean my diamond ring as well?