A method of operating an arc discharge lamp and a lamp in which a light
transmissive envelope encloses electrode tips, a salt and a fill that
includes iodine, and in which after turning the lamp off, a first part of
the light transmissive envelope is locally cooled relative to other parts
of the light transmissive envelope to provide a condensation site for the
iodine that is spaced from the electrode tips, the first part of the
light transmissive envelope being where a salt reservoir forms and where
the salt is cooled by the local cooling. The local cooling may be
provided by an indentation in an outer sleeve around the light
transmissive envelope, where the indentation contacts the first part to
provide a heat sink.