No idea if this is official, but it is mentioned in a Reuters article:
Silver-coin shortage shows bright side of precious metal collapse
NEW YORK/LONDON/SINGAPORE, Sept 30 (Reuters) - The global silver-coin market is in the grips of an unprecedented supply squeeze, forcing some mints to ration sales and step up overtime while sending U.S. buyers racing abroad to fulfill a sudden surge in demand.
The U.S. Mint began setting weekly sales quotas for its flagship American Eagle silver coins in July because it can't meet demand, and the Canadian mint followed suit after record monthly sales in July. In Australia, the Perth Mint sold a record of more than 2.5 million ounces of silver this month, nearly four times more than in August, and has begun rationing supply of a new line of coins this month, a mint official said.
"Silver demand is absolutely through the roof," said Neil Vance, wholesale manager at the Perth Mint. "There seems to be a bit of frenzy as people think there is a shortage of silver. But in fact it is a (crunch in) manufacturing capacity."
While demand has risen in response to the slump in spot prices to $14.33 an ounce in late July and its subsequent drop to fresh six-year lows below $14 an ounce in August, mint officials also said they were caught out by the sudden interest in coins. In July, the U.S. mint halted sales for almost three weeks after running out of "blanks", which are used to make coins.
Some investors like to own physical metal to protect from volatility in other assets, particularly currencies and stocks, and to hedge against geopolitical and economic upheaval. The CBOE Volatility index, or VIX, of U.S. stocks - popularly known as the "fear index" - briefly jumped to its highest since January 2009 earlier this year.
At the U.S. Mint in West Point, New York, where the American Eagle is made, the plant is operating three shifts and paying staff overtime, a spokesman said.
The Austrian Mint, which has begun allocating sales of its Philharmonic silver coins, has increased production of silver blanks after higher-than-expected demand in July and August, a spokeswoman said.
In his 35 years of dealing precious metals, Roy Friedman, vice president of sales and trading at Manfra, Tordella & Brookes, one of the biggest U.S. wholesale coin dealers, said he could not recall seeing a squeeze in supplies of North American silver coins spilling over to coins made in Austria and the U.K. to the degree seen this year.
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PLUNGING SILVER
Still, the rush of coin buying has failed to offset a years-long silver rout by institutional and retail investors betting on further gains in the dollar, U.S. equities and an improving U.S. economy.
Prices have fallen 7 percent this year, are on track for their third yearly loss and down by 70 percent from all-time highs of $50 hit in April 2011.
Holdings in the silver-backed exchange traded funds, , which were popular with investors during the financial crisis that followed the collapse of Lehman Brothers, sank to below 518 million ounces this week, their lowest in almost three years.
For now, however, coin dealers are riding the wave. Bullion dealers around the globe who typically offer next-day delivery are now taking silver coin orders several weeks out.
"I don't expect things to get better until next year," said Gregor Gregersen, founder and director of retailer Silver Bullion based in Singapore. (Reporting by Marcy Nicholson in New York, A. Ananthalakshmi in Singapore and Jan Harvey in London. Editing by Josephine Mason and John Pickering.)
More: http://www.reuters.com/article/2015/09/30/silver-collectors-idUSL1N11Y1FM20150930