Firstly, there isn’t a single mid-price when you come to sell your bullion.
The spot price has ‘bid’ and ‘ask’ prices attached to it to see the highest and
lowest offer prices that bullion dealers will give you for your precious metals
at that specific point in time.

The bid & ask prices imply the costs of trading and are determined by supply
and demand. The prices are also set by market powers and influencers.

** EXAMPLE **
If you're searching for the price of gold or silver online, you might come across
different prices. A quick google search might show that gold is at $2,036, but a
trusted dealer might list it as $2026.50. This is determined by market makers
(e.g. COMEX). If this is not confusing enough, what about when you see two
prices that are next to each other, such as, $2,020.85/ 2,025.16?
This is the bid/ask price.

‍

The first number, the bid price, refers to the price at which a buyer is willing to
purchase a specified quantity of gold or silver at a given moment. It represents
the demand side of the market, indicating what buyers, like precious metals
dealers, are willing to pay you for the product you already own.

‍

On the other hand, the second number, the ask price, represents the price at
which a seller is willing to sell their gold or silver. It reflects the supply side of
the market, indicating the price at which precious metals dealers are willing to
part with their precious metals.

‍

Important note: The Bid and Ask prices typically do not include any premiums
that may be involved in the transaction.

Hope that helps you out ....

Al Varelas / USMC
SS-1654
Member: PCGS
Member: NGC
Member: CAC