1888.] PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 125 



No. 5992:5. Ornauieut, Sardinal. Pale olive-green, compact, not granular, specific 

 gravity 2.65, Taylor. 



No. 59856. Ornament, Las Huacas. Bluish green, mottled, not granular, specific 

 gravity 2.621, Hallock. 



No. 59845. Ornament, Nicoya. Like 59857, but darker, specific gravity 2.62, Tay- 

 lor. 



No. 59932. Ornament, Sardinal. Grayish green, faintly translucent, not distinctly 

 granular, specific gravity 2.62, Taylor. 



No. 59937. Ornament, Panama, Costa Rica. Like 59932, specific gravity 2.62, Tay- 

 lor. 



No. 59955. Ornament, Boquerones, Costa Rica. Like 59932 and 59937, specific 

 gravity 2.60, Taylor. 



No. 328. Ornament, Ometepec Island, Lake Nicaragua. Brownish, highly polished, 

 specific gravity 2.593, Hallock. 



No. 59855. Ornament, Las Huacas. Like 59856, specific gravity 2.589, Hallock. 



No. 59860. Ornament, Las Huacas. Dull bluish-green, opaque, specific gravity 

 2.377, Hallock. 



No. 59858. Ornament, Las Huacas. Dull light-green, soft, specific gravity 2.324, 

 Hallock. 



No. 59912. Ornament, Sardinal. Like 59858, specific gravity 2.30, Taylor. 



No. 59894. Ornament, Sardinal. Dull grayish green, soft, specific gravity, 2.294, 

 Hallock. 



No. 59868. Small ornament, Nicoya. Dark green, specific gravity 2.29, Taylor. 



No. 59899. Ornament, Las Huacas. Dark green, not mottled, soft, specific gravity 

 2.282, Hallock. 



No. 59924. Ornament, Sardinal, dull green, not mottled, soft, specific gravity 2.266, 

 Hallock. 



It will at once be seen that these objects, as regards density, fall into 

 three pretty well defined groups. The highest values represent jadeite, 

 more or less impure, and of various qualities ; the middle group is near 

 quartz in specific gravity, and some of its members certainly belong to 

 that species; the lowest division contains ill-defined substances, which 

 are also characterized by softness. 



Four of the objects, viz, two jadeites, one quartz-like mineral, and one 

 of the softer stones were selected for more complete investigation. The 

 supposed quartz, JN"o. 60048, from Eio de Buena Vista contained 97.10 

 per cent, of silica, 1.85 per cent of alumina and oxide of iron, no lime, 

 and no magnesia. No further examination seemed to be necessary. 

 The jadeites, Nos. 59927 and 28992, however, were more interesting. 

 In composition they are as follows: 



