Description of the Most Principal Mineral Ores

Floerz original: "Floßerzte" of various colors

of silver. All floßerzte superficial/deposit ores, be they yellow, white, brown, blue, green, or gray; item, copper lazur, copper or mountain green, and copper glass; these hold in part silver as well, but the coarse lazur and mountain green are generally poor and not rich in silver. In sum, all silver ores and mine-types that do not have pyrites, blende, cobalt, mispickel, mica, wolfram, coarse bismuth, speiss, copper-speiss ores, or similar hard-fusible ore within them, are all called soft-fusible, mild, and malleable ores and mine-types.

Pyrites of various kinds.

Conversely, all pyrites are counted and named among the infusible ores. Whatever is coarse pyrite, water pyrite, or cubic pyrite, they hold little silver, and for the most part by themselves without disseminated silver ore, no silver, or at least not much, over one loth half an ounce. Copper pyrite, yellow like brass, brown and blue-tarnished pyrite, hold much copper, as one will find in the report on the copper metal, and such pyrites also hold silver, yet one kind more than the other; one also finds such copper-rich pyrites that hold no silver at all.

Cobalt ore

All cobalt, be it solid, or mild, flaky, or spherical, black or gray, is sometimes rich in silver, sometimes also very poor.

Mica and cat-silver.

All poor common mica, also persistent iron-mica, Talga a type of soft talc or greasy mineral, and Katzensilber cat-silver/muscovite, they are very poor in silver, although sometimes the black blende is rich in silver; yet such blendy and micaceous ores are in general poor. And I consider them a true bloom of other metallic ores.

Bismuth ore.

All coarse bismuth ores, which one also calls speiss-ores, likewise the small-speiss bismuth ores, from both of which in smelting the coarse speiss comes forth, they are generally by themselves very poor in silver and hold many times nothing at all.

Spatose mine-type.

All spatose original: "spatigte" ores or mine-types, be they red, yellow, green, or white, they hold without other disseminated silver ores for the most part nothing, or no silver at all. Also, the raw slag-stone, as well as copper-stone, speiss, and furnace-break, which come from the layers of the aforementioned pyrite-ores and mine-types, also from the raw layers in smelting, are counted among the hard-fusible, stubborn silver ore assays.

Slag-stone and furnace-break.

However, how the aforementioned soft-fusible, likewise the hard-fusible silver ore assays, are to be made differently, that...