300 Description of a New Mineral called Haytorite. 



" The forms," says Mr Levy, " and mere inspection of the 

 ensemble of the measurements of Haytorite prove that we may 

 assume for the primitive form an oblique rhombic prism, the 

 lateral planes of which would correspond to the planes ^, Fig. 

 9, and the base to the plane m, this base being inclined upon the 

 lateral planes at an angle very little greater than a right angle." 



By comparing the angles of the secondary form, calculated 

 from the above primitive form, with those obtained by Mr 

 Phillips, Mr Levy remarks, that the differences are so small, 

 that it may be inferred at once, that the crystals of Haytorite 

 are perfectly regular, and that one of the forms, which may 

 be taken as their primitive, can differ but very little from an 

 oblique rhombic prism, the incidence of the lateral planes of 

 which is 115° 16', the incidence of the base in each of them 

 90° 8' 30", and the lateral edge equal to the oblique diagonal 

 of the base.'" 



" When I first saw," continues Mr Levy, " the drawings and 

 measurements of Haytorite, I thought they might be consi- 

 dered as pseudomorphic crystals of sphene, because some of 

 the angles are not very far from those of that substance ; but 

 the preceding investigation proves, that an almost perfect equa- 

 lity must be established between the angles of Haytorite, and 

 those of any other mineral, before it can be reasonably sus- 

 pected that the crystals of the first have only borrowed the 

 form of the other ; and therefore, the above suggestion must 

 be abandoned. The only substance between the angles of 

 which and those of Haytorite there seems to be a great ana- 

 logy, is Humboldtite. First, by inverting the drawings of Mr 

 Phillips, the similitude of the forms of Haytorite with those of 

 Humboldtite, represented by Mr Phillips in his Mineralogy, 

 \ p. 380, becomes apparent. The planes P, g l 9 d, h, k, i, n, v, 

 of Haytorite, correspond to the planes h, m, a,f, e, e, a x >g x > 



of Humboldtite, and have the following inclinations, according 

 to Mr Phillips : 



