Fig. 



it's properties and composition MUNRO 15 



The first slide showed 

 a blue gel with little 

 colorless crosses here and 

 there. These little cross- 

 es were found to be in- 

 cipient crystals, for, on 

 the second slide exam- 

 ined, cross and square 

 crystals, derived from 

 these, were found side by 

 side. The third slide 

 (Fig. 2) showed these 

 crystals in large numbers. 

 In many cases the cross 

 could be seen, forming 

 the diagonals of the square. This cross pattern reminded one 

 of sim.ilar pattern found in a variety of the minerals, Andalu- 

 site, Chiastolite. The crosses in the mineral are supposed to 

 be caused by "impurities on crystalization" (Butler). It 

 seems more reasonable in the case of a Molybdenum compound 

 that they are the edges of an octahedro i. If this be so, they are 



molybdic oxide. A few 

 colorless hexagonal crys- 

 tals were also noticed. 

 These were recognized as 

 ammonium molybdate. 

 The photograph shows 

 these crystals, some hex- 

 agonal ones, as well as 

 gel and amicrons. 



A portion of dialyzed 

 hydrosol was evaporated, 

 at 18°. The deposit on 

 slide was examined under 

 microscope. A beautiful 

 back ground of blue gel 

 was seen. This gel con- 



FiG. 3 



