make nickel yellow (some people are allergic) osmium will be probably covered by layer of toxic tetroxide, cadmium and tellurium are also decently toxic

e: i misremembered, but you still don't want to be around tellurium:

Humans exposed to as little as 0.01 mg/m3 or less in air exude a foul garlic-like odor known as "tellurium breath".[23][91] This is caused by the body converting tellurium from any oxidation state to dimethyl telluride, (CH3)2Te, a volatile compound with a pungent garlic-like smell. Volunteers given 15 mg of tellurium still had this characteristic smell on their breath eight months later. In laboratories, this odor makes it possible to discern which scientists are responsible for tellurium chemistry, and even which books they have handled in the past.[92]

selenium is a bit similar in this aspect