54 



THE GUIDE TO NATURE. 



Mineralogical Review. 



BY C. ROE GARDINER, 1 6/ HOOPER ST., 



BROOKLYN, N. Y. 



( )n Chlormanganokalite, A New 

 Vesuvian Mineral, with notes on 

 Some of the Associated Minerals. 

 By H. J. Johnston-Davis, M.D., B. 

 Sc, M. R. C. S.. F. G. S.; and 

 L. J. Spencer, M. A., F. G. S. Min. 

 Mag., XV, 54. 

 This new Vesuvian mineral, found 

 amongst the products of eruption, was 

 previously described in "Nature" of 

 May 31, 1906. A large amount of 

 Chlormanganokalite was discovered on 

 breaking up two large masses of ma- 

 terial that had been ejected from this 

 volcano during an eruption. 



An analysis on some of this new 

 mineral gave the following results: 



K Mn CI Me Na SOr H2O Insoluble 

 36.34 11.52 40.13 .04 0.38 0.81 1.52 0.71 = 99-4 



The calculated percentage compo- 

 sition in which allowance is made for 

 the presence of admixed sylvite corre- 

 sponds to the probable formula 4KCI. 

 M11CI2. 



On Determination of Mineral Consti- 

 tution Through Recasting of 

 Analysis. By Alexis A. Julien, Ph. 

 D., Annals N. Y. Acd. So., XVIII, 

 129; April, 1908. 



This interesting paper gives food 

 for thought in regard to the chemical 

 composition and formulas assigned to 

 many of the minerals in our text-books 

 on mineralogy. All who are familiar 

 with minerals as viewed through a 

 polarizing microscope know that 

 homogeneity in crystals is rarely if 

 ever seen, and in probably a great 

 man}-- cases where analyses of min- 

 erals have been printed in literature 

 these specimens were never examined 

 by the microscope and consequently 

 it was nearly impossible to allow pro- 

 perly for foreign impurities. 



The following is an example of the 

 method used in recasting the analysis 

 of a mineral : 



"Thermophyllite." 

 From Hopansuo, Finland. Average 

 of three analysis by Arppi, Hermann 

 and Northcote, with the formulas. 



(RO.3R2O3) 2SiOs + 2H2O and (MgO.HO) + MgO.SiO.s 



In association with this mineral were 

 found sylvite, halite and hematite. 

 ( >n Strtiverite and Its Relation to II- 



menorutile. By G. T. Prior, M. 



A., D. Sc, F. G. S.; and Dr. F. 



Zambonini. Mix. Mac,., XV, 78. 

 Struverite occurs on the Prano dei 

 Lavonchi and in other localities on the 

 Eastern slope of the mountain across 

 which runs the road from Vasco to the 

 All) Marco. The mineral is found in 

 pegmatite as a rare accessory constit- 

 uent. 



Ilmenorutile, a mineral recently rec- 

 ognized by Brogger as a definite 

 species, was discovered on the Ilmen 

 Mountains, Urals, in 1854. 



The formula deducted from analyses 

 for struverite F2O. (TaNb^Or,. 5Ti02 

 and for ilmenorutile FeO. (NbTaH'Or,. 

 5Ti02 indicate the close chemical re- 

 lationship of these two minerals. 



Two New Boron Minerals of Contact 

 Metamorphic Origin. By A. 

 Knope and W. T. Schaller. Amer. 

 Jour. Scl, XXV, 323. 



On the northwest Hand of Brooks 

 Mountain on the Seward Peninsula, 

 Alaska, was discovered a new boron 

 mineral for which the name hulsite 

 has been proposed. 



The other mineral for which has 

 been proposed the name paigeite was 

 found at Brooks Mountain and also 

 forty miles northeast at Ear Mountain. 



The formula calculated from an- 

 alysis for hulsite is 9FeO. ^Mg TO. 

 2Fe20s. 2H2O. 8B2O3. 



The formula assigned to paigeite is 

 6(FeMg)0. Fe2O.-5.H2O. 3B2OL 



Note: At a lecture delivered before 

 The Brooklyn Institute of Arts and 

 Sciences by Dr. Schaller on February 

 2nd, he suggested that due to the fact 



