UPDATE 1-Newspaper inserts possible investment - Barron's

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NEW YORK, June 28 (Reuters) - As newspaper advertising supplements go down in number, their value as collectibles has shot up, making them a possibly hot but least known alternative investment, according to Barron's.

While many supplements are glorified press releases and others hawk various items, some have sported "exquisite style and panache, accompanied by riveting graphics," the report said. Such supplements command up to $10 million a page in the collectibles market, the report said.

As an example, the report said a single mint-condition copy of "Greek Soccer to Boost Betting" now gets upward of $2.5 million.

The report also warned against fake versions of magazine inserts that have begun to surface.

Newspapers have been facing dwindling circulation in past years, as many readers go online for news content. But with newspapers and magazines disappearing, and with most old papers preserved only on microfilm or online, physical copies of vintage ad supplements are rare, the report noted.

(Reporting by Aarthi Sivaraman; Editing by Phil Berlowitz)