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SCIENCE-GOSSIP. 



MINERALOGY. 

 By John T. Carrington. 



"\I 7E often wonder why so comparatively few 

 persons in this country take up the study 

 of Mineralogy. As a study, or even as a hobby 

 for collectors, it is deeply interesting. The speci- 

 mens are often things of great beauty, and a 

 knowledge of the different kinds cannot fail to be 

 of value to those who have opportunities of visiting 

 little known lands. 



These thoughts were vividly impressed upon us 

 during a recent visit to the collection of Mr. Thos. 

 D. Russell, of 78, Newgate Street, London. We 

 remembered how many persons there are who 

 would be better for taking up some hobby, numbers 

 of these people are young, and could not have a re- 

 creation which will prove more valuable in after life. 



Among Mr. Russell's specimens we were shown 

 an exceptionally brilliant and showy series of 

 Calcites from Cumberland ; especially some trans- 

 parent twin crystals. These are called " butterflies " 

 by the miners, from the nearly symmetrical appear- 

 ance of the cleavage planes within the mass, which 

 looks as though silvery butterflies had been caught 

 and entrapped within the crystal, like the flies 

 seen in amber. Other Calcites were tinted reddish- 

 brown by hematite ; the specimens being taken 

 from iron-mines in Cumberland. From the same 

 district were some lovely pieces of specular iron, 

 with quartz crystals ; one especially handsome one 

 having a flat basis of specular hematite, with a large 

 quartz crystal resting upon it, in fine contrast, which 

 was found with the others in the Cleator Moor 

 Ironworks. With these were some richly-coloured 

 examples of Pearl-spar or Dolomites ; some being 

 "golden," and others with tints running through 

 brown into pale lemon yellows. Zinc blends were 

 also associated with quartz and pearlspar in 

 other specimens. Also from Cumberland were 

 some remarkably beautiful specimens of Calcite, 

 sprinkled with a delicate incrustation of coloured 

 iron pyrites. The iridescence from the faces of 

 these minute pyrites is very brilliant, showing 

 hues of golden green, blue and bronze-red. Near 

 these are found tabular crystal masses of Byerite, 

 in white, blue and brownish-yellow. 



From Herkimer, County New York, in the State 

 of New York, was a fine series of doubly-terminated 

 diamond-like crystals of quartz, most brilliant in 

 appearance. By them were a number of Utah 

 Topaz crystals in the matrix ; these occurred both 

 transparent and vinous-coloured. From Mexico 

 were a number of examples of the transparent 

 colourless variety Hyalite of Opal, which has the 

 appearance of groups of small drops of oily water 

 piled up one on the other. Other American 

 minerals included masses of Iron pyrites in cubical 



crystals associated with Magnetite, Calcite and 

 Byssolite, an unusual combination from Pennsyl- 

 vania. The uncommon mineral, Rhodochrosite, 

 associated with Copper pyrites, was from Colorado. 

 Rutile paramorph, after Brookite, was from Arkan- 

 sas, perfect specimens of these dark geniculated 

 crystals forming a kind of rosette. There were 

 also specimens of the iron-black octohedrons of 

 Martite, from Utah, with lovely pieces of Chalco- 

 trichite or velvet copper. 



Among the more peculiar minerals are the 

 Chalcidonic geods, containing fluid with which the 

 pieces are only partially filled, so that it may be 

 seen through the semi-transparent mass. It is a 

 most interesting form of silica in small sponge- 

 like masses from Uruguay. Another and very 

 different variety of silica is tbe "liver opal," or 

 Menilite, so called from the locality, Menil 

 Montant, near Paris, where it is found. Speci- 

 mens are like compressed flints covered with a 

 smDoth incrustation of calcareous marl. From 

 France, also, Mr. Russell has received some fine 

 "cross-stones," or Staurolite, which occurs in 

 Brittany. Norway contributes some polished speci- 

 mens and cleavages of Thulite, a pink and white 

 variety of Zoisite. This mineral, when polished, 

 makes handsome ornaments ; for instance, a casket 

 of Thulite was included in the wedding presents 

 of the Princess of Wales. 



An imposing group among the novelties of this 

 collection was of " peacock " coal, which is highly 

 iridescent ; it came from Barnsley, in Yorkshire. 



The last new mineral is named Lorandite. It is 

 sulpharsenide of Thallium associated with Realgar, 

 and found in Macedonia. The only other known 

 Thallium ore is named after its discoverer, Crook- 

 site, Professor Crooks, F.R.S., being the first to 

 identify this mineral. Mr. Henson, of Regent Street, 

 has some fine specimens of this rare and beautiful 

 mineral. He has also now on view some half-inch 

 crystals in the matrix of the very scarce mineral 

 Whewellite, transparent oxalate of lime. It is a 

 closely allied mineral to Thierschite, if not actually 

 identical, which occurs as an incrustation. Such 

 large crystals of Whewellite do not seem to have been 

 previously observed, as hitherto they have only 

 been found of almost microscopic size. These fine 

 examples are from Saxony. 



Mr. James R. Gregory, the well-known mineralo- 

 gist, has migrated with his business to the neigh- 

 bourhood of the Kensington Museums and Science 

 Schools. His firm's address is now 1, Kelso Place, 

 Stanford Road, Kensington, W., which is within 

 easy reach of High Street, Kensington, and 

 Gloucester Road Stations. 



