maez, colour wise, i will suggest u do not take anything below G. And for clarity, is VS2 and above. B'coz, any grade below G & vs2 for colour & clarity respectively, u can see from the naked eyes the slight "yellowish" colour & impurities under certain lighting. unless the stones are too small to see.
a full tennis bracelet of 6.7 pointer, will come up to a total of >3ct.
as for citigems stones, they are cheap for a certain reason. is not just the branding. u can just ask the citigem staff, they can tell u the colour & clarity of their stones. Also, your eyes do not play trick.. u can see quite clearly the inferior quality under the lighting.
a 0.5 ct stone of reasonable colour & clarity (ie, G & VS1) easily cost $3k plus after 40% discount. and i am not even talking abt the elite range like brilliant rose range. usually, the prices jump very substaintially, once it hits the 0.5 ct, 0.7 ct, 1 ct and so on category.
anyhow, just for reference only.