Bekaunite - -FKOivr Danbakagan, Western Australia. 
133 
11.— BERAUNUl^]- FIKIM DANDARAGAN, WE81MBiN 
Al^STRALlA. 
By C. R. Le Mesuriek, A. A. CM. 
Read 8th April, 1 941 : Ihibliwlied 20tli May, 1942. 
The occurrence of phosjjhatc minerals at Dandaraj^an was first officially 
reported by \\ . D. (/ampljoll iu MMXi (I). They coinprisi^fl tht; iron phosphates 
Dufrenite and Vi\'ianite and the aluminium phosphate Waveliite, besides 
beds rich in coprolites and apatised wood. 
In 1932 the late Hr. K. S. Simpson visited the area and colkictod sjiociniens 
of a new mineral, a hydrous basic jihosphate of |)otas.sium and aluminium, 
which was named Minyulite, after Min.\'ulo Well lu^ar which it was found (2). 
The subject of the ]iresent paper, Beraunite, a iiydrous ferric pliosphate 
with the formula 2b e^(OH );^( PO^).2.5H _.() was collected by Mi‘. K. Ftirman from a 
locality known as 1 he C'av'cs, ’ about 2^ miles N.F. of Vandan Hill, during a 
recent inspection of this area. 
The towaisfiip of Dandaragan lies 22 miles by road west of Moora, which 
is 106 miles north of Perth on the Midland Railw^ay. 
For the following description of the mode of occurrence of the Dandaragan 
Bei’aunite the author is indebted to Mi’. Forman, Government Geologist. 
The mineral is exposed on the face of a bluff about 50- 60 ft. higti, (Binposod 
m the lower 30-40 ft. of ferruginous sandstone overlaid by co])rolito bearing 
sandstone 3-5 ft. thick whicJi is in turn capp(‘d by what is probably greensand 
(glauconite bearing sand). 
The ferruginous sandstone is impregnated to a depth of from 2-3 ft. below 
the coprolite bed wath dark green dufrenite while the beraunite is confined to a 
nariow zone, not more than 3 inches in width in the upper surface immediately 
underlying the (coprolite beds. See section. 
Probable Creepsond S . (^o/>ea / 
C. C Perounde o Perruginoi/sSonrj 
The mineral occurs as radiating fibres with a silky lustre enclosed betw’eon 
w^alls of lustrous black limonite in irregular veins varying in width from 2 
to 5 mm. 
The colour in mass varies from Ridgways 13’k, Russet to 2V"n\, dark 
olive. Hardness, 4-5. Specific gravity, 2*95. 
Under the microscope the fibres are transparent, wath opa(iue blotches 
due to adhering limonite, wliicli has penetrated between the finest fibres. 
