II. A. Ward — Colombian Meteorite localities. 5 



5ir kilograms was secured from the Bogota Museum, where 

 the main part of this meteorite resides. The Rasgata locality 

 lies near Cipaquira at a distance of ten leagues from Bogota, 

 and a little to the west of a line between that city and Santa 

 Rosa. 



In view of the considerable distribution claimed for the 

 Santa Rosa iron among the various museums, it is an interest- 

 ing fact that the most careful scrutiny of its exterior before 

 cutting failed to reveal a single place whence even -the smallest 

 piece had been removed. The accompanying cut describes 

 better than words the general shape and appearance of the 

 siderite. Its three dimensions are 71 am , 49 cm , and I6 cm . The 

 entire natural surface of the mass is covered with shallow sau- 

 cer-like depressions which give it an undulating appearance. 

 Other sharper-walled and deeper pits show by the troilite often 

 to be found occupying their bases, that they have been formed 

 by the weathering away of mineral accessories. A thin semi- 

 lustrous coating, grading from brownish-black to rust-brown, 

 encases the siderite and represents a somewhat altered natural 

 crust. The small end of the block is interesting in a quite 

 different way. Here, as may be seen in the cut, the crust has 

 been removed, the projections smoothed down, and the pitting 

 effaced by the battering of the smith's sledge, during long ser- 

 vice as an anvil. The piece secured was taken from this end, 

 and the slicing has been carefully made so as to preserve the 

 anvil portion, — a historic as well as beautiful specimen, — for 

 the Ward-Coonley Collection. 



Immediately upon my return to this country, I sent a speci- 

 men of the Santa Rosa iron to my friend, the eminent author- 

 ity, Dr. Brezina, and shortly afterward received the following 

 in reply : 



"This iron (Santa Rosa) corresponds exactly with the descrip- 

 tion given by Professor Cohen. It consists of differently oriented 

 grains 2 to 3 cm in diameter, which are separated by very fine 

 fissures filled with schreibersite or (rarely) with magnetite (Eisen- 

 glas). The grains are formed by octahedral lamellae of kamacite 

 nearly free from taenite and plessite, but rich in skeletons of 

 schreibersite crystals. The lamella? average a thickness of 2 to 

 2 - 5 mm . The kamacite is strongly hatched and grained, the diam- 

 eter of the grains being - 05-0 - 10 mm , and presents a great num- 

 ber of dimples so as to show a vivid oriented glitter. Troilite is 

 scarce, one bulky plate measuring 2xlO mm . 



Along the natural surface an alteration-zone of - 5-2 mm thick- 

 ness is seen, which is dull ; outward of it, on one corner, a scori- 

 aceous bark of half-molten iron a millimeter in thickness is seen. 



Cohen gives an analysis made by Sjostrom, which shows — 



