Loose diamonds aren't necessarily cheaper than their mounted equivalent, however, they have the advantage of offering buyers a 'complete view' – no inclusions hidden by prongs or color concealment against a setting. Buying a loose diamond online will be considerably cheaper than buying from a store.

Wholesale diamonds are cheaper for a few reasons. First, they are sourced directly from diamond mines or cutting factories, which cuts out the middleman and allows the buyer to save on markup. Second, because they are sold in bulk, wholesalers can offer a discount on the per-carat price.

so, depending on your buying range. but India is the cheapest followed up by China, Dubai, Thailand, and Belgium. they are the cheapest because most of the world's diamonds are cut there. so you do not have to pay any markup due to shopping or retailer markup.

One of the most traditional choices is to sell to a pawn shop, jeweler, or diamantaire (diamond dealer) at a brick-and-mortar store location. In order to make a profit as a retailer, they will pay you a portion of your diamonds' retail value, and then sell them for a higher price.