The following is an email letter from a RCM distributor concerning the problem. To summarize, the RCM's position on "milk spots" on their silver coins is : "Don't like it? Buy something else."
Here is the short explanation. We just had a meeting with the Mint about this 10 days ago.
The white stains (or "milk spots") result from the planchet (flan) cleaning and preparation process. Some Silver Maple Leaf coins have them (SMLs), some do not.
This is the Mint's official position: The coins are bullion coins. They are not collector coins. They are sold as one ounce of silver. The Mint knows that there is a problem. The problem has existed since 1988, when the SML coin was first introduced. The Mint says that there is nothing that they can do about the problem.
Our experience is that some SMLs have them and some do not. We do not know what we are going to get when we open the boxes of 500 ounces of silver that come from the Mint. We have to take what we get; we can not return them. We do not have the time to sort them, etc.
We ship out what we get. Per the terms of our invoices, we do charge a restocking fee for returned bullion items.
I am sorry about the problem, but we have no control over it.
I hope that this helps,
ANA Life Member
Official Distributor for the Royal Canadian Mint,
for the Mint of Poland (in Warsaw),
for the Perth Mint of Australia,
and for Monnaie de Paris (The Paris Mint)
9051 Watson Road, Suite 103
St. Louis, MO 63126
UNITED STATES OF AMERICA