I don’t see anything that looks like radium lume there.

Generally, radium paint materials will be whitish and thickly printed, or seen as a fill material in hour markers and hands, or small round dots next to hour markers. With age, it will darken, so sometimes it’s now tan or grey-green, but it will be a light color, and often looks chalky.

The radium paint itself is a mixture of a zinc sulphide based phosphor, radium salts, and organic paint binders, like an oil paint. The bulk of it is zinc sulphide, which is a white, chalky-looking material, so that’s what the paint looks like. To make zinc sulphide into a radioluminescent phosphor, it’s chemically altered with a trace amount of either silver or copper. Copper based phosphor can age greenish, but a lot also depends on how the paint binders age. Being organic compounds, and exposed to a lot of radiation from the radium content, they usually darken or yellow, just like old lacquer exposes to direct sunlight, resulting in a light brown color for the aged radium paint. The zinc sulphide itself breaks down from the radiation, so it stops glowing even though the radium salts remain radioactive.