A SCRAP collector and locksmith got the surprise of their lives after discovering an old family safe filled with hundreds of gold and silver coins.

The anonymous Houston collector took the safe to locksmith David Molick and asked him to break into the vault before it was turned into scrap.

Mr Molick then spent 20 hours breaking into the safe, drilling through six-inch concrete walls, before uncovering the secret stash of money.

"He showed me a picture of this safe, and I saw that it was a high security one," Mr Molick told abc News.

"It was real difficult to get into. It was pretty beat up. Looked like somebody had tried forcing their way into it since the front was beat up."

He said he didn't think the money was real at first and estimated the safe must have weighed around 1500kg and contained about $2.5m.

The locksmith called police who took possession of the money before it was handed back to the unidentified family who owned the safe.

Police would not confirm the amount of money inside, only saying it was "substantial".

The family's lawyer Mike DeGuerin said the father had been saving the coins for decades but had recently died.

The safe was uncovered during a garage clean up and was to be sold as scrap.

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