New-York tribune., 1841-04-14
THE LEAD MINES OF IOWA.

THE LEAD MINES OF IOWA.
A small volume entitled Sketches Of Ioo, by John B.
Newha mas Just been given the public 1t full OF IN
tenstng information rcspec, Iowa and our Western
Country generally We from the following account
of the Lead Mines and Mining in Iowa:
GALExA (sulphurae of ead) be divided into three
classes or descriptions according the relative per cent OF
the pure metal yielded by each.
The first class is that wicl, lies the surface of The
ground and consequently the first species OF discovered
l. known among the miners BY the OF ash mneTd
IN account of lis being covered with substance IN appear
ance similar TO white ashes This substance appears 10 p
carbonate Of the protoxyde OF lead II Is generally i'und
in small bodies the depth OF sN or eisht inches from me
surface and Immediately under the first strata OF soil and
ly;no in horizontal sheets Of about inch and half in
thickness.
The fact of this ore living the surface of the ground
in which situation it must necessarily cone IN contact win
less oxygen atmospheric a readily accounts 10Y
It's being covered with this ashy substance.
This description of ore is generally found near the
highest elevation of the bluffs and by the horizontal position
of the sheets the edge becomes exposed to view by CON
tned wasncs of the rains and thus leads TO the discovery
of the entire sheet This description o therefore, was
easily discovered when the mining region was irst explored
the pioneer; might, by ploughng or spadins up small
garden open the sight large pieces OF the sparkling
This species OF lead is for entitled 10 be called
the first class first yields, average from eighty 10
eghvve per cent of pure lend while the other descriptions
of ore at the highest yield but about scyenivc
six per ccntun, and sometimes but from forty to nifty
Secondly. because the first species discovered ana
the only the Indians previous the settlement
of the country by the whites being OF pure quality that
they enabled 10 run it into bullets and ornaments with
the simple aid OF their log fires 1t is obtained with the least
expense of the varieties of although found in
as large bodies that which lies farther from the surface the
of the sheet seldom if exceeding 10000 pounds
weight and most generally OF about onc-icnth that size.
The second class OF lead may be found soft clay
Immediately above the secondary rock. depth ranging
.I..
perhaps the reader that the formation OF the earth
in the mining region composed of mixed combina
ton of enrhs than almost any other part Of the sobying
In regular above the primary rock In sinking shaft
(Which generally Of small dimensions convenience will
allow being about three and halt 10 four feet in damecr)
the miner finds, for the first three feet soft light
brown clay which the depth OF three feet generally be-
mixed with small pieces OF white flint and, he de-
scends, the flint gradually increases in size the clay AT the
same time becomes of darker red ochrcl>h color
At the depth of five feet he finds the flint changed into dep
blue color, and formed into regular sheets oi about TWO and
half three inches in thickness generally about three sects
lying horizontally above each other and separated by strata
OF reddish clay ol about three inches IN thickness After sink
ing through these suaia flint the clay becomes o brighter
red, and mixed with kind of spurious ore, frequently
great proportion carry the appearance o solid bed
Of rust or oxvde of iron his thickness
than that Of any other being frequently eight feet thick and
at others entirely Disappearing below this strata lies soft
dark-brown clay sometimes mixed III vacSatcd maine!
with small seaks of green rcd blue white and yellow clay
The yellow OF clay has The appearance al me llotoNNd
of Iced and the only coloed clay found in the
as above mentioned which i frequently eighteen
inchc. in thickness and regular than the other coor
The clay this depth is OF moist nature and Is found
immediately above the sand secondary rock and incrn
sed with ii; About eighteen inches above the rock found
what is called bv the miners ct'Vk mineral, deriving
name from the form which i found having the appear
Ance being thrown together without regularity being found
in chunks OF regular shape. VARYING m size from halt an
ounce weight 1000 pounds his species OF mineral :
treef fr1rnp
greater quantities han the ash mineral. and consequently
Yields the metal. the beng about
scventy-ve per cent this however. i found IN large
bodies sometimes nteruNed With clay for the thickness of
eight feet and from the Sofnes> OF the clay. taken from
the earth with great facility. Wien the miner has sunk hi
shaft the bottom OF the minerals ne drifts each way from
it. BY digging the earth for space o four FIVE feet
width by three III hight. until ne 10 The extremity OF
the body of mincral he then cror:i>. leaving few
pillars for the support of the clay above until he obtains
the ore sometimes however. anxious that nothing shall
be lo he leaves an insufficient support and j. obliged
wooden props stays keep the earth from ayug in upon
him. This generally found yng at the head Of
vine the surface OF the ground Immediately II has
appearance. and when the >eei place for
sinking shaft he descends short distance from the
MT where the cia! OF depth. where The
onaTy rock Is oi softer and regular
nation. The OF clay which the chunk lnine,.
found into the hill frequently forms horizontal
opening between the sand rock which the mineral assume,
the OF regular sheet, and lies the top OF the strata
clay and partially adhere the upper rock winch may be
considered somewhat singular whc; : known that the ore
is about the specific gravity Of the clay and would
naturally be looked for underneath this OF CLAW The
sheet thus formed between The rock generally Of mon
han one inch in thickness. and Of limited unless il
meets with perpendicular oaas the rock IN
which case often iesccnd> this until reaches
another horizontal hs>ure crevce in which forms
ronal sheet of gre
Third CIa<s-This shee, or strata generally found from
forty to sixty feet depth It har! ana solid varying ro.
,wo inches to three feet thickness and forty siNy
feet in length varying also much width. Miners
led 10 Tie discovery OF this species Of IN the pursuit o: