Assertion: alexandrite's color | /r/HasProperty | seen with unaided eye
Facets:
Source sentences:
text: Stated otherwise, the color seen with the unaided eye when looking parallel to any of the three crystallographic axes is always a mixture of two of the X, Y, and Z basic color components (Schmetzer and Bosshart, 2010; Schmetzer and Malsy, 2011).