TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Catalysts: Catalysts (I) with a BET surface of 10-500 (preferably 40-150) m2/g and an integral pore volume of more than 100 (preferably more than 180) mm3/g, in which the amount of metal particles in (B) is 0.1-5 (preferably 1-2) wt.% and the amount of (B) in (I) is 5-50 (preferably 10-15) wt.%. Material (A) is a metal oxide, preferably titanium, aluminum, tin, zirconium, cerium, silicon, zinc or aluminum-silicon oxide, or a magnesium silicate or a mixture of two or more of these. The metal particles in (B) consist of transition metals, preferably manganese, cobalt, nickel, iron, rhenium, ruthenium, osmium, rhodium, iridium, palladium, platinum, copper, silver or gold, especially precious metals, in the form of particles with an average diameter of 0.5-5 (preferably 0.5-2) nm. The dispersion of metal particles is 0.5-20 (preferably 1-10) %. %. The zeolite (B) corresponds to one of the following structural types: AFI, AEL, BEA, CHA, EUO, FAU, FER, KFI, LTL, MAZ, MOR, MEL, MTW, OFF, TON and MFI. The catalyst may be in the form of powder, formed pieces or a monolith, and/or supported on a carrier. Preferred Method: The method includes a fixing stage (a1) between stages (a) and (b) in which the metal is fixed on the zeolite, preferably by calcining or by converting the metal compound into the metal. A final stage involves stabilisation of the supported catalyst (I). EXAMPLE - Zeolite with a platinum content of 1.5 wt.% and a BET surface of 450 m2/g (I) was obtained by ball-milling a mixture of commercial zeolite powder (BEA type; ammonium form; LOI = 8 wt.% at 1000 degrees C) and platinum chloride for 1 hour, heating to 500 degrees C at 1 K/min and maintaining this temperature for 12 hours under slightly reduced pressure. A combination of 12 g (I) and 88 g commercial support material (Al2O3, La2O3 and CeO2) was intensively mixed to give material (S1) with a BET surface of 120 m2/g. A washcoat suspension with an average particle size of 3 microns was obtained by wet-milling S1 with water; this was applied to a commercial cordierite honeycomb material (80 cpsi) by immersion and blowing out followed by calcination (12 hours at 500 degrees C in air), to give material with a washcoat content of 80 g/l, which was then calcined for 12 hours at 500 degrees C under hydrogen, to give a final catalyst material with a platinum content of 1.44 g/l. This was cut into two cylinders with a length of 10 cm and a diameter of 1 inch, one of which was subjected to artificial ageing (24 hours in air at 800 degrees C). When exposed to a mixture of nitrogen with 2000 ppm propane and 8 vol.% oxygen (500 degrees C; space velocity = 150000 v/v), the unaged catalyst gave a propane conversion (oxidation) of 98 (99) %, compared with 91 (48) % for the aged catalyst. Values in brackets are for a similar catalyst in which the washcoat suspension was a wet-milled mixture of zeolite, support material and platinum chloride powder (rather than platinum-chloride-loaded zeolite).