Spots on coins Mikulov


In 2022, collectors and investors could buy gold coins of the Czech National Bank with a face value of CZK 5,000 dedicated to the Mikulov Urban Monument Reserve.

You may already know that a number of owners have discovered unsightly red spots on these coins (in both standard and proof versions). If you have purchased coins with Mikulov, we ask you to examine them carefully.

In case you find stains, please visit one of the branches of the Czech Mint in Prague, Brno, Jablonec nad Nisou or Bratislava. Our colleagues will take the coins from you (each must be packed in its original capsule and etui, but keep the certificate with you) and arrange for their exchange for perfect pieces.

Attention - we are only able to make the exchange if you hand in the defective coins to us by 15 April 2023.

What is "gold rust"?

Pure gold does not corrode. So how is it possible for it to show stains?

The manufacturer of the casing - or blanks from which we mint coins at the Czech Mint - uses its tools to work with a variety of materials. In addition to gold, these include silver. Therefore, it is possible that trace amounts of silver adhere to the gold sheet during rolling, which then turns into red silver sulphide.

We are very sorry to hear about our supplier's error. Please be assured that our technologists are doing everything possible to prevent this unpleasant situation from happening again...

Thank you for your understanding.

Czech Mint team

Pochybení našeho dodavatele nás velmi mrzí. Ujišťujeme vás, že naši technologové dělají vše pro to, aby se tato nepříjemná situace neopakovala…

Děkujeme za pochopení.

Tým České mincovny

Czech Mint