Tintin, that indefatigable (cartoon) boy-reporter created by the Belgian Hergé (George Remi) in 1929, has captured the hearts and minds of children and adults for the past 90 years. He's also snared the attention of a devoted group of deep-pocketed collectors. 

Last month, a double-page strip from King Ottokar's Sceptre sold for 1.6 million euros ($1.7 million) at Sotheby's in Paris, and a record was set the year before when original art for Tintin and the Shooting Star sold for almost $3 million at the Brussels Antique Fair. 

This weekend, Tintin will face yet another test as dozens of Tintin-themed lots hit the auction block at Artcurial, a Paris auction house whose stately headquarters look out onto the Champs-Élysées. The top lot is an extremely rare original plate from Tintin Au Congo (a 1930-1931 serialized comic-cum-book that glorifies Beglium's appalling colonial history, turns the Congolese into racially problematic caricatures, and, as icing on the cake, plugs big game hunting).

It carries a high estimate of $550,000, an amount Eric Leroy, the specialist who organized the sale, describes as reasonable for the current market. "It's not uncommon to find drawings by Hergé for more than half a million" euros, he says. "There's an Hergé museum and they have maybe 98 percent of his production; original plates are very hard to find."

Leroy estimates that there are only 40 to 50 original plates on the market. "The real problem," he says, "is to find masterpieces to put in auctions, because people have collected for a long time, and they hold on to what they buy."