Whether it was an indicator of optimism or of money looking for a safe investment, demand proved high enough at the March auction sales to drive prices up despite the continually gloomy economic forecast. Of the top 20 lots sold, ten posted auction records for the maker: four for Sotheby’s, three for Brompton’s, and three for Bonhams.

Brompton’s once again had the high flyer of the London spring sale season, a violin by Pietro Giovanni Mantegazza, Milan, circa 1770, which hammered at £185,000—more than three times the old auction record. The violin belonged to a Los Angeles–area physician who, throughout a distinguished career in medicine, performed for decades as concertmaster and soloist of his local orchestra. “It sounded phenomenal,” Bromptons specialist Jamie Buchanan says.

Sound, however, rarely drives prices on the violin market—attribution is the leading determinant of value. And this instrument had early W.E. Hill and Son papers attributing it to Andrea Guarneri, later amended to Joseph Filius Andrea Guarneri. But, as violin expert Philip Kass says, “At the time, [the Hills] didn’t know 90 percent of what they knew 20 years later.”

Kass is glad to see a Mantegazza sell under its true name at a price that reflects its real quality. “They are wonderful instruments,” he says, and hopes that at this price more of them can stop masquerading as Guarneris. Of course, this pulls the prices of properly attributed Mantegazza instruments out of reach of most string players.

“[These sort of sales are] always a bad day for musicians,” Kass says.

Part of the thrill of an auction is the possibility of a “sleeper,” something really good that is mis-attributed or overlooked by the auction house. Bonhams provided a classic example: lot 195, catalogued as simply “An interesting silver-mounted cello bow” with an estimate of £800 to £1,000. The handsome head had been broken and pinned.

So why the £26,400 sale price? The devil’s in the details, and one of the details was that the Parisian eye on this bow had a tortoiseshell ring between the pearl dot and the silver ring—characteristic of F.X. Tourte, aka the “father of the modern bow.”

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