Rolex GMT from 1968 tritium dial / zinc sulfide hands

[springer]

In response to your your question regarding your lume, the possibility exists that the lume is original - which is the zinc sulfide variety that normally glows green under the UV light test. 1968 seems to have been a transition year for this type of lume.

Also, be aware that the hands could have been changed to hands that contain zinc sulfide lume or, the hands were relumed with a type of lume available on the internet which can be purchased in several color variations to include green.