Phenakite group - PL spectra Phenakite group Index IR-Reflectance Photoluminescence UV-Vis-NIR Phenakite: Colorless phenakite - 0.50 ct - Unknown locality Eucryptite: Gray eucryptite/albite – 1.56 ct – (Londonderry, Nepean, Coolgardie), Australia Willemite: Very-light-yellow willemite – 0.42 ct – Franklin, New Jersey, USA Colorless phenakite - 0.50 ct - Unknown locality No photoluminescence with the sources: 254, 370 & 405 nm. Gray eucryptite/albite – 1.56 ct – (Londonderry, Nepean, Coolgardie), Australia exc 277 nm: 698 nm - Fe3+ Very-light-yellow willemite – 0.42 ct – Franklin, New Jersey, USA exc 254, 277, 405 and 442 nm: 525 nm - Mn2+ replacing Zn2+ in tetrahedral site
