Sandy mines, Sandy Mines group, Jefferson County, Missouri, USAi

Regional Level Types
Sandy mines	Mine
Sandy Mines group	Mining Sub-district
Jefferson County	County
Missouri	State
USA	Country

The Sandy mines are located in the N 1/2 of section 18. They were discovered in 1824, and were quite extensively worked during the early years. In 1826, they produced 450 tons of ore, and up to 1866 had yielded 5000 tons. As examined by Litton at that time, the diggings extended about a mile in a direction somewhat east of north. The deepest shaft was 115 ft., passing first through 14 to 30 ft. of surface clay, and then into a bluish earthy limestone.

The ore in the rock occurred in a vertical crevice which expanded and contracted so that the galena was mined from a series of connected cavities. These enlargements were found at three different levels. The crevice remained perfectly well defined between these, however. The ore was principally galena, but some cerussite was mined, and, at times, blende and pyrite were found. Broadhead describes the deposit as a nearly vertical fissure running N-S., from a knife edge to 17 inches wide, with a wall-rock of magnesian limestone. This, he states, was filled with barite and galena. It had been traced for several miles. He reported two other fissures parallel to this, a few hundred feet apart.

These mines have been worked, at intervals, for a number of years. The diggings extend over a line nearly one mile in length, the course of which is a little east of north and west of south; though the principal part of the work has been done on some 500 feet at the south end.

The ground is covered with clay, the thickness of which varies from fourteen to thirty feet. Below this, judging from the debris thrown out, are some beds of impure, blueish, argillaceous limestone.

The deepest shaft has been sunk 115 feet; drifts have been run between some of them at two different levels. A short time ago a, pump and engine were put up to drain the mine; but at the time of my visit, operations had been intermitted by the person who now has a lease and has been working it for some year and a half.

Above the rock considerable quantities of mineral were obtained, some twenty years ago, but all on the same north and south line, and even extending into the rock. In the rock the mineral seems to exist in a vertical fissure, and, so far as I can learn, not continuous from top to bottom, but principally accumulated at three different levels.

At the first point, at which mineral is found, in the rock it is represented as having a vertical range of six or eight feet, below which the fissure partially closes to a depth of from six to ten foot, when it is again found to widen out and contain mineral, in a vertical range of ten or twelve feet. Below this the fissure again partially closes for a depth of ten or fifteen feet, and at this point mineral is again found, with a vertical range of from fourteen to twenty-five feet. I am assured that the fissure is well defined and distinct from one level of mineral to the other. Of the yield of this mine since 1840, Mr. Coolidge is unable to give any definite and accurate statement, as the furnace in the neighborhood has, during his period, belonged to different persons. By one who was working for the present lessee, I was informed that, during the present year, about 30,000 pounds of mineral had been obtained; and from Mr. Coolidge I learn that, in 1842 and '43, several thousand pounds of mineral were raised; and, in 1846 and '47, some 300,000 pounds; and at other times considerable amounts, of which we can give no accurate account.

The ore is the sulphuret, with small quantities of the carbonate, and sometimes accompanied by yellow iron pyrites and zinc blende.