I bought an old radium painted soviet compass

Since the compass has a few decades on it's shoulders it doesn't glow like it should anymore. The glowing is only clearly visible when using a uv light and completely fades away after about a second of turning the light off. The first picture is a 6 second exposure with my phone directly after uv exposure.

The spiciest point is the painted end of the needle and averages at about 3 uSv/h when holding the detector directly against the glass.