The Birmingham age-herald., 1912-11-09

verified and a portion of each sample re- tained by competent and disinterested persons.
 "The most important feature of general interest to be found in these results is the effect of this new information upon the estimates of the iron ore reserve of the Birmingham district. and since the future growth and prosperity of the dis trict will no doubt largely depend upon the magnitude of the ore reserve, any in- formation upon the subject is of great i'm portanee.
 Tn bulletin 400 of the United States geological survey MT. Ernest F. Burchard made an estimate of the red ore reserve of the district based on information at hand up to January. 1909.
 The only area considered in this esti- mate comprised the ore along the outcrop on Red mountain from Morrow gap to Sparks gap and extending back to Shades mountain.
 An Old Theory
 Tn making this estimate the theory of original deposition of the ore in a shallow bay CT sea was used, and under this the. ory, as MT. Burchard says. it is fair to assume that at a certain distance from the outcrop the ore begins to thin out The beds would thus form long, thin.
 
 of the wedge lying along the outcrop on Red mountain with the thin edge. some what less regular In outline, lying far to the southeast. Even the approximate po- sition of this line. which represents what may be termed the thin edge of the ore, is very uncertain.'
 For the sake of conservatism, and in the absence of definite information, Mir Burchard assumed for the purpose Of the estimate that Shades mountain would mark the boundary of workable ore.
 Burchard's Computation His computation of the tonnage of ore was then made upon the assumption that the ore was a wedge shaped body, the thickness of the base being represented by the thickness of the ore at the out crop, and the point of the wedge reach ing to about the crest of Shades noun lain. He also assumed that the ore would not be workable when its thickness came below three feet So this placed his limit of workable ore approximately along Shades creek. In classifying thu reserve MT. Burehard estimated sepa- rately
 @d) Ore which can be reached by slopes from Red mountain.
 "(2) Bottom bench, inferior ore, avail able to slopes from Red mountain "(s) Ore in Shades valley which win be won by shaft mining
 His estimates are as follows.
 Gross tons. Available red ore reserve ..,.... .s5S, ITO, TOO Lower bench big seam ...... .146, CA, TOO Shades valley, not at present
 available .s..................,... 2o2, fol 400
 - Total .......................... .79e, ,Sa6. 800 The Shannon McDonough drill dole Is almost in line with the No slope of the Tennessee Coal, Iron and Rail- road company. The thickness of the upper bench at that mine as given by MT. Burchard is nine feet four inches. shale parting one foot eight inches, and lower bench not given, but is about three feet thinck.
 Thicker and Better Ore
 Therefore the condition Is shown that instead of a thinning of the ore going southeast, as assumed in the computations we have at a distance of nearly three miles thicker ore and bet ter quality.
 Tt Is obvious that the effect of such information is to practically double the probable ore reserve in the area upon which the estimate was made, and if the theory of original disposition is the correct one, there is indicated an ini- mense body of ore entirely outside of that area lying to the east of Shades mountain.
 'As to the question of availability, MT. Burchard had good reason to con sider ore at depths of from 150o to 2000 feet as not available at present when the thickness was assumed to be from six feet down to three feet. but when the thickness is shown to be nine feet the proposition is quite diff ferent.
 As to Operating Economy
 Sinking 2o00-foot shaft. through the easy material found in Shades val ley offers no serious difficulties. and the question becomes one of the ad- ditiona1 capital investment necessary for development The interest on such increased capital would probably be more than offset by reductions in cost of mining due to working a Hat seam and moving a greatly increased lon- mage as compared With results obtained at slope mines on the outcrop
 Tt seems that better classifica- ton from the commercial standpoint would have been based on quality; the self-huxing or the near self-fuxing ores, in seams exceeding six feet in thickness, might be considered as first class ore. It is this ore alone from which pig iron can be made at a suf- helently low cost to meet the low prices prevailing in times of commercial de- pression, and it is matter of experi- ence that only those companies who own mines in the elf-fuxing district are able to successfully tide over the periods of extreme depression In the iron market,
 In the Course of Time
 Tn time, and with the growth of the southern market for iron, there will doubtless be a condition developed when the southern states will be able 10 consume all of the iron manufactured in the Birmingham district. When such Is the case better prices for pig iron will be realized and much of the slice GUS ore will become available
 At the present time, however. hard red ores requiring more than 25 per cent of limestone to Aux them cannot be considered immediately available, although small tonnage of such ore is at present mined for the purpose of reducing the excess lime in the self fuXing ores in cases where the first class ore Is slightly over self nuxfng It would seem, from commercial standpoint, better to classify such ore as second class or not immediately available.
 Large Figures
 The writer is fully aware of the fact that it would be premafllre to