A self-contained portable device (1) for lighting an item (9) capable of sparkling, such as a jewelry item, a timepiece, a craft object, or any other similar item, comprises an easily manipulated mounting (3, 4), having at least one rectilinear edge, and a lighting system (2). The mounting comprises a flat bottom (4) surrounded by edges (3) defining a space (4) wherein an item (9) to be illuminated is capable of being placed, at least one of the edges (3) being rectilinear. The lighting system (2) comprises a plurality of light sources, at least one of which is a warm white light-emitting diode and at least one of which is a cold white light-emitting diode. Said light sources are placed in an elongate body (2') mounted on one end of an adjustable movable arm (10). The other end of said arm is connected or connectable to one edge (3) of the mounting. One rectilinear mounting edge (3), comprising an elongate recess (7) along the outer surface of said mounting, is sized so as to receive said elongate body (2') of the lighting system (2) in order to enable it to be built into the mounting in a rest position of the device. The lighting system (2), when taken out of the recess (7), is arranged so as to illuminate an item (9) placed anywhere within said space on the bottom (4), along with the illumination oriented in a variable manner depending on the orientation of the movable arm (10) and the angle whereby the elongate body (2') is angled relative to the arm (10).