cát = sand . Cát mango got its name, because its skin looks like sand with all the dots color when ripe.
We have Xoài cát ( Cát mango) has more than 2 varieties and they are Xoài cát Hòa Lộc ; Xoài cát chu ; Xoài cát bồ; Xoài cát núm ; Xoài cát thơm . Most of these Cat mango varieties are for eating ripe.
We have Xoài tượng ,Xoài Thái, Xoài Đài Loan which well known for be eaten green. Xoài Thái origin from Thailand. Xoài Đài Loan origin from Taiwan
Xoài bao tử / Xoài cóc are small size fruits, well known for being eaten green or making pickles.
There are many other varieties of mangoes in Viet Nam, but the most well-known for the best Vietnamese mangoes are Xoài cát, Xoài tượng
There is no Xoài cát Saigon and No Xoài cac. When you say " Cac " the sound in Vietnamese is meaning male private part in a dirty way to say.