Show OPAL MINES OF H HUMBOLDT COUNTY by maynard bixby the opal deposits owned by mathewson a and nd associates now in salt lake are situated in the extreme northern part of humboldt county nevada north of the black rock desert and consist or of two full mining claims these two claims are located on two low hills near the top of which the opal is found in a blanket vein running from six to eighteen feet in thickness the situation being in proximity to various hot springs and the large la rge number of fossils and pieces of and wood found would lead the observer to the opinion that the opals originated in hydrothermal hydro thermal action but expert examination will enable a more definite conclusion the opals have so far been mined with the pick from an open cut on each claim and may be mined for several years in a similar nillar si manner A miner may take out about fifteen pounds per day with a pick more or less of which is cutting material the opal matrix has been pronounced by the U S geological survey and is soft appearing mostly like a yellow sandstone but in some places harder and resembling obsidian the greater part of the cutting material occurs in separate masses and is easily parted from its loose matrix quite a large proportion of the pieces are alterations of wood and specimens in possession of the writer show complete sections of tree limbs parts of which show handsomely colored gem opal while other parts show the grain of the wood in great perfection c van cn splitting into slivers perfectly much of this wood opal is the lare variety and of gem quality showing the various beautiful opal tints the body of the stone being milky white while similar to the hungarian precious opal these specimens when placed in water for a half hour emit bubbles of air becoming becom ipg transparent so that print may be read through them and on removal from the water resume their normal appearance pe arance still showing their opalescent colors when thoroughly wet of grayish colored body and full of fine opal tints occurs and this also becomes transparent in water almost every variety of gem opal existing elsewhere in the world is found in these deposits opals of a brilliant black color are common common and black stones with a fine brilliant play of the various green red purple and other opal colors aie found clear fine stones with a magnvil magnall cent play of brilliant tints resembling the best mexican of this sort are common some stones of all varieties show very at brilliancy of coloring and some could be well called flaming opals stones from these deposits are the most attractive and brilliant I 1 have seen from any american locality and the only veritable american black gem ovas opals that I 1 have yet seen are from this property green or chlor opal occurs showing gem colors as well as honey opal smoky shades blue and brown and a great variety of milky opal most beautiful pieces are found on the surface still s showing howing the most brilliant play of splendid colors after their long exposure to the desert climate salt lake utah U tah march 10 1911 |