Part 18

§ 157.

ARGENTUM nativum (ſilver native), united to iron. Native.

§ 158.

ARGENTUM nativum (ſilver native), united to arſenic. Native.

The arſenic hardly exceeds ⁶⁄₁₀₀.

§ 159.

ARGENTUM nativum (ſilver native), united to antimony. Native.

When melted, it ſmokes but has no ſmell of arſenic.

§ 160.

ARGENTUM nativum (ſilver native), united to arſenic and iron. Native.

The three metallic ingredients are nearly in equal proportions.

All the ſpecies hitherto mentioned have metallic properties and appearances. The contaminating matters are ſometimes extremely ſmall, but not to be neglected when they exceed ¹⁄₃₀₀ part of the maſs.

§ 161.

ARGENTUM (ſilver) mineralized by the vitriolic and muriatic acids. Hornlike.

CRONSTEDT Min. §177. Minera argenti cornea. Horn-ſilver.

Mr. WOULFE, detected the preſence of the vitriolic acid. The ſilver ſeldom exceeds ⁷⁰⁄₁₀₀. I know not whether it is ever altogether free from vitriolic acid.

§ 162.

ARGENTUM (ſilver), mineralized by the vitriolic and muriatic acids, and ſulphur.

I doubt whether this be a diſtinct ſpecies, ſince the ſulphur and the ſalts ſcarcely admit of any other than a mechanical union.

§ 163.

ARGENTUM (ſilver), mineralized by ſulphur. Glaſſy.

CRONSTEDT Min. § 169. Minera argenti vitrea.

It ſometimes contains ⁷³⁄₁₀₀ of ſilver, or more.

§ 164.

ARGENTUM (ſilver), mineralized by ſulphur and iron. Marcaſitical.

CRONSTEDT Min. § 176, 10. Pyrites argenteus.

§ 165.

ARGENTUM (ſilver), mineralized by ſulphur and lead. Potters.