GENERAL CHARACTER OF VEINS. 123 
total production of the Appalachian States from 1800 to 1900 is considered to be $47,000,000. 
For the last few years the total annual production has been about $300,000, while the pro- 
duction of Georgia has varied from $130,000 to $60,000, the latter figure being recorded in 
1903. 
GENERAL CHARACTER OF THE VEINS. 
As already pointed out by Eckel, many of the gold deposits lie on the contact either of 
mica schist and amphibolite or of mica schist and granite. This does not apply to all of 
them, however, for some, like the Jumbo and Garnet, are entirely inclosed in mica schist. 
Of the three rocks, the mica schist is the oldest and the granite the youngest. The 
quartz veins are later than the granite and appear to exhibit a certain relationship to that 
rock in their occurrence. At no place are the veins located far from the granitic intrusions; 
even at the Jumbo mine, which is wholly in mica schist, granite outcrops only a few hundred 
feet away. The veins follow the schistosity in strike and dip, although at each deposit 
there are many stringers of quartz which cut across the division planes of the rock. 
The deposits are in part "stringer leads," to use Becker's expression, and in part dis- 
tinct veins, composed of a series of flat lenticular bodies of quartz, usually strictly conform- 
able to the schistosity and following even its minor curves. The familiar, sharply cut fis- 
sures of the western veins are absent. In some cases the veins are corrugated or curved. 
As Becker has pointed out, all this shows that there was a certain degree of correspondence 
between the forces which produced the schistosity and those which opened the fissures. 
The quartz is, as a rule, compact, milk-white or even glassy, and shows normal coarse, 
hypidiomorphic vein structure without evidence of much crushing and shearing even in 
the veins which appear bent and curved; drusy places with projecting crystals are not 
uncommon; comb quartz is rare, although occurring in some narrow seams which cut across 
the prevalent fissures, as, for instance, in Preacher Cut. Much of the bright-yellow gold is 
coarse, and forms, without doubt, a primary constituent of the ore. The sulphides are 
relatively poor, but in the oxidized zone they have naturally contributed their quota of 
gold to enrich the ore. The sulphides associated with the quartz are pyrite, chalcopyrite, 
and zinc blende; pyrrhotite occurs sparingly. In the Benning vein magnetite occurs 
anhedral or in octahedral crystals and intergrown with pyrrhotite, chalcopyrite, calcite, 
and chlorite; pyrite is also contained in the quartz. Of gangue minerals there is some cal- 
cite or dolomitic carbonate; in many places in the Benning veins this lies along the wall, 
as it commonly does in California veins. Garnet, apatite, ilmenite, muscovite, dark-green 
mica, and green hornblende occur in the altered wall rocks of some veins, but also in places 
directly in the quartz. Dark-green zinc spinel or gahnite in octahedral crystals is embedded 
in quartz with free gold and small foils of sericite from the Rosamund vein of the Standard 
group. 
Gahnite is a rare mineral and, like spinel, usually occurs in gneisses or as a result of con- 
tact metamorphism. It is not altogether unknown in mineral deposits, for Genth « describes 
it from the Cotopaxi mine, Chaffee County, Colo., associated with pyrite, galena, and chal- 
copyrite, and containing inclusions of chalcopyrite. A. G. Dana b mentions an occurrence 
of gahnite from the Rowe pyrite deposit in Massachusetts. This is a lenticular vein in 
gneiss, and the gahnite occurs partly in the pyrite and partly lining cavities subsequently 
filled with quartz. It is here associated with apatite, ilmenite, rutile, epidote, garnet, cal- 
cite, triclinic feldspar, pyrite, and sphalerite. 
In the lenticular veins pay shoots occur similar to those elsewhere found in gold veins, 
and Mr. Joe Clement informs me that the rule in Dahlonega is that they pitch to the left of 
an observer standing on the croppings and looking down along the dip. 
The wall rock adjoining the quartz at many places contains enough gold to be classified 
as an ore, though, as a rule, the principal values are considered to be contained in the quartz. 
In the same veins garnets, hornblende, apatite, and a green mica may develop along the 
quartz vein, as shown, for instance, at the Lockhart mine and several other places. The 
a Am. Jour. Soi., 3d ser., vol. 23, 1885, p. 455. & Proc. Am. Phil. Soc, vol. 20, 1882, p. 397. 
