A unique collection of stamps and other postal materials that underwent decontamination in an attempt to prevent the spread of disease will be on display as part of an international philatelic exhibition in Jerusalem from May 8 to 11. The exhibit will include a letter sent from Venice in 1459 that is the first proven to have been decontaminated before being opened. Sterilization of mailed envelopes to protect against anthrax, the Black Plague, cholera and other diseases was common practice until recently, even though the decontamination methods were ineffective. The collection belongs to Dr. Hedy Feivel, whose items survived spraying with vinegar, ironing and other attempts at decontamination. Tens of thousands of unusual, rare and valuable stamps and related items will be on display at the exhibition at the Jerusalem International Conference Center, organized by the Israel Postal Company's Philatelic Service and the Israel Philatelic Society. Every visitor to the event - admission is free - may purchase a 12-stamp sheet to be issued in its honor and add a drawing or photo, or a caricature drawn by an artist on at the exposition. Also for sale will be a sheet of six stamps showing the planets that form a puzzle - individual stamps can be rearranged to create a drawing; a lottery will be held to choose prizewinners. Collections are being brought from the US, Sweden, Denmark and Greece, as well as from local collections. The Eretz Yisrael Museum in Tel Aviv will put on show a collection covering the history of the pre-state Yishuv, including postcards written by Binyamin Ze'ev Herzl to his daughter and letters by Moses Montefiore. Amir Levin will display his very rare collection of Doar Ivri stamps from 1948, while Shlomo Stern will present his collection of philatelic material from the Soviet Union between 1923 and 1938, considered the world's best. An international panel of judges will present medallions to the best collectors. The exhibition will be open from noon to 9 p.m. from Monday May 8 to Thursday May 11. Organized tours for schoolchildren will begin every morning at 9.