Mineral Point tribune. [volume] (Mineral Point, Wis.) 1854-1858, 1854-05-11

cation. Occasionally, however they ine line down
wards or upwards for few feet. but their din is
very irregular. These fat sheets have been very
productive in many localities. Good examines
occur at Mineral Point, Dodgeville. Ii lden. Mes
sersmiths and Blue Mounds They are usually
connected both above and below with vertical
veins. Both these classes seem to have a speciaI
geological position. Thus the perpendicular veins
with large openings and caves, are nearly confined
to the gray limestone. The middle ard lower
beds carry flat openings and fat sheets, while flat
sheets alone are found in the bufI,colored lime
stone.
Chunk m'ueral aaolt mineral and apatch
mineral" are broken sheets which have been left
BY the decomposition of the rock, which once in
closed them and are now found in the loose ma
terial Of tie surface.
VEIN STONES.
Ii the perpendicular veins, the ors is usually
unaccompanied by any ofthose substances known
as vein stones. The fiat sheets aowever..are usll
ally associated with some mineral substance. which
is the matrix Of ore The most common of these
substances are tiff black jack, dry bone, iron pyr-
ties, ochre, barytes. These accompany the lode.
either singly or combined in varying quantities:
sometimes filing the entire vein even and taline,
he place Of the ore and at other times entirely alb
sent or very slightly developed The arrangement
OF these substances is often in parallel layers call
cd combs. In such cases the succession is cuite
irregular. The ore IS sometimes upon one side
OF the VEN, and the veinsonc upon the otheror it
runs between the layers of It's matrix. dividing of
ten into several branches In other cases the ore
and reIu-stone are mingled in one mass recurring
The process of roasting and stamping to separate
them. The vein stones present often a great prac-
teal difficulty 10 the working of mines, by their
irregular distribution. In some instances veins
have been followed for distance, and yielded pure
ore, but suddenly vein stone set in which en-
larsed until It "eat out the ore, as the miners ex
press i, and the matriy alone remained. This
alienation Of the ore and It's matrix
has ruined tie prospect of many miner, and in
veins thus Affected great caution and sound iudg-
ment are required. The vein is quite sure to WELD
pure ore again at some point ahead but the most
profitable method Of reaching it depends upon va
rious circumstances. Ia many cases where this
substitution Of the vein stone occurs. the ere i
found dispersed through the adjacent rocks in
small cubes along the line Of the barren portion
Of the vein. These cubes are often very abundant
and are called "dice mineral" Instances Of this
character may be found at Mineral Point, Shulls-
bureh WiHgvii!e, Crow Branch Diggines, sc.
Il is difficult TO determine which ofthe substan-
ees spoken Of above, is tie most favorable ulica-
lion Of a good lode, Heavy deposits of ore have
been found wish all Of thern or entirely free from
any associates, and there Is probably no necessary
connection between either ortlesn, and the barren
ness or productiveness of the veins which they ac
coHn}aE--