Pseudomorphous - Occurs in the form of another mineral.
Hardness:
2 - Gypsum
Streak:
yellow gray
Optical Properties of Plumbotellurite
Gladstone-Dale:
CI meas= -0.082 (Poor) - where the CI = (1-KPDmeas/KC) CI calc= -0.088 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1755,KPDmeas= 0.1745,KC= 0.1614 Ncalc = 2.16