@Abhishek,
Based on your natal horoscope, you can wear the red Coral, Pearl and Yellow Sapphire.
American diamond as Moon sign lord, was ok, but as per the Janam Kundali (Natal Horoscope), you should not wear it as it is Marak (Death/evil inflicting).
You don’t need to wear Emerald as per your natal horoscope; also, Emerald should not be worn with Pearl and Red Coral.
Yellow Sapphire goes well with Red Coral and Pearl and usually contradicts with Rahu and Emerald.
My advise is to wear Red Coral, Pearl and Yellow Sapphire.
Wishing you good luck, may God bless you and above all?
Cheers