28 
THE SPRING HILLS’ AND CENTRAL LEADS MINE, 
JERUSALEM, NEAR ALLENDALE. 
(no. IS on locality map.) 
By E. J. Dunn , F.G.S., Director , Geological Survey , Victoria. 
Professor Gregory’s paper, published as Bulletin No. i of the Geo¬ 
logical Survey of Victoria, has dealt so thoroughly with the geology of 
this area that but a few details remain to be considered. The general 
sequence was that during a long period of denudation the great Berry 
River—a broad and powerful stream—and its tributaries eroded the Ordo¬ 
vician rocks down to what is now the bed of the deep leads. In the 
process the softer rocks were ground down to sand and clay, and carried 
off by the river, while the harder material, the fragments of quartz derived 
from the lodes that seamed the slates, sandstones, &c., were ground to¬ 
gether, and all the more friable portions worn away until only the hardest 
portions of the quartz remained as great, well-rounded boulders and pebbles 
—some of the boulders ranging up to 2 or 3 tons in weight, and many of 
them running from one to several hundredweights apiece. The most abun¬ 
dant, however, are what Professor Gregory aptly describes as “ cannon 
shot,” the well-rounded quartz pebbles that form the bulk of the wash- 
dirt. Between the pebbles is finer drift material, and throughout the 
wash-dirt is a little clay, just enough to make it adherent. This is a cha¬ 
racteristic of good wash-dirt, and throughout such the particles of gold are 
disseminated from top to bottom. When, the gravel is clean washed, and 
free from this small amount of clay, there is usually an absence of gold 
also. Actual sections of the wash-dirt are as under: — 
CO^/?S£ C/ft £ G/?/Uf£L 
(C£M£A/rf£>J. 
'WCAO/AfGS' 
O O 0 C o 
'o°o 
° o O ‘ ‘ • 0 -o 6 O 
AA/PC CCATC Z OM£/?A££ o ~ ° . o o ° ° ° ~ ^ o 
fC£M£Vr££>J. o yO "f o ° , 0 O - - 
cca/?s£ oa/px- o 0 ° p ® o O ° a C O 
CCCC£//?£D £0(/CC£/?S & ° 0 (J) ° _ W, ° o _ c? ° 
ot <D°'° ° 
g/f/c/rcsc/A' cOjloJ. 0 <0 q (_/ a 
pass// rvooc. 
O 0 C 
°o ° r . o2vr 
o O 
cO o O “ 
(D^OaP O’Oqo 
C/?££ SAPS A/VC 
C/?/£ 
g£A/.S£ -£££>£££>J. 
MO££/?A££-£/£££> C/?A££C, 
tV/r//AXGf/lAA’£/?ACM£//rs :. c 
- 4 ‘. 
uuhhyVUhiihoUo.'- .2 c? 
/ 3; 
C/?£K c/?/r. 
c/?£y£/Ar£-c/?/t/#££>£>#/££. \ - ■; • • v.;.vh:/.’• 
/>//>£- CC/JK ^ 
S/.A££ £££>S 
tb/?oo p/c/a ny. 
Pig. 7. 
2: 
AASALT. 
In extracting the wash-dirt, the large boulders of quartz are left below. 
Some of these are never moved, as thev are of immense size. Mr. R. 
Smyth, of Allendale, formerly the mining manager of the Ristori Creek, 
