Process for preparing a precious metal catalyst, wherein said process comprises the steps of: - reducing a precious metal compound selected from palladium or gold in an aqueous solution at a temperature ranging between 10°C to 95°C, by contacting said solution with a reducing agent, a stabilizing agent and a coordinating agent selected from the group consisting of urea, ammonia and combination thereof thereby forming a colloidal precious metal suspension; - contacting the suspension with a powder support selected from the group consisting of silica, alumina, zirconia, titanium oxide, ceria, magnesium oxide, zinc oxide, metal silicates, metal aluminates, zeolites, carbon nanotubes, carbon nanofibres, graphitic carbon and activated carbon and combinations thereof; and, - recovering the precious metal catalyst, wherein the reducing agent and the stabilizing agent comprise of one compound or more than one compound which acts as both a reducing agent and a stabilizing agent, wherein said catalyst comprises nanocrystallites of a precious metal on a powder support, wherein the precious metal is palladium or gold metal; and the powder support is selected from the group consisting of silica, alumina, zirconia, titanium oxide, ceria, magnesium oxide, zinc oxide, metal silicates, metal aluminates, zeolites, carbon nanotubes, carbon nanofibres, graphitic carbon and activated carbon and combinations thereof; wherein the palladium metal catalyst comprises nanocrystallites having an average size between 1 and 4 nm as measured by Transmission Electron Microscopy, and wherein said catalyst has a surface enrichment value of from at least 6.5 to at most 150; and, wherein the gold metal catalyst comprises nanocrystallites having an average size between 3 and 13nm, and wherein said catalyst has a surface enrichment value of from at least 3 to at most 150, and, wherein the surface enrichment value (SEV) is determined from the following formula (I): SEV = XPS wt . % − ICP wt . % / ICP wt . % ; wherein XPS wt.% is the X-ray photoelectron spectroscopy (XPS) measurement and ICP wt.% is the inductively coupled plasma (ICP) measurement of the precious metal content in weight percent of said catalyst, and wherein XPS wt.% and ICP wt.% are determined according to the description. - reducing a precious metal compound selected from palladium or gold in an aqueous solution at a temperature ranging between 10°C to 95°C, by contacting said solution with a reducing agent, a stabilizing agent and a coordinating agent selected from the group consisting of urea, ammonia and combination thereof thereby forming a colloidal precious metal suspension; - contacting the suspension with a powder support selected from the group consisting of silica, alumina, zirconia, titanium oxide, ceria, magnesium oxide, zinc oxide, metal silicates, metal aluminates, zeolites, carbon nanotubes, carbon nanofibres, graphitic carbon and activated carbon and combinations thereof; and, - recovering the precious metal catalyst, wherein the palladium metal catalyst comprises nanocrystallites having an average size between 1 and 4 nm as measured by Transmission Electron Microscopy, and wherein said catalyst has a surface enrichment value of from at least 6.5 to at most 150; and, wherein the gold metal catalyst comprises nanocrystallites having an average size between 3 and 13nm, and wherein said catalyst has a surface enrichment value of from at least 3 to at most 150, and, wherein the surface enrichment value (SEV) is determined from the following formula (I): SEV = XPS wt . % − ICP wt . % / ICP wt . % ; <EOS>