What is "fulminating silver"

Silver \Sil"ver\ (s[i^]l"v[~e]r), n. [OE. silver, selver, seolver, AS. seolfor, siolfur, siolufr, silofr, sylofr; akin to OS. silubar, OFries. selover, D. zilver, LG. sulver, OHG. silabar, silbar, G. silber, Icel. silfr, Sw. silfver, Dan. s["o]lv, Goth. silubr, Russ. serebro, Lith. sidabras; of unknown origin.]

1. (Chem.) A soft white metallic element, sonorous, ductile, very malleable, and capable of a high degree of polish. It is found native, and also combined with sulphur, arsenic, antimony, chlorine, etc., in the minerals argentite, proustite, pyrargyrite, ceragyrite, etc. Silver is one of the ``noble'' metals, so-called, not being easily oxidized, and is used for coin, jewelry, plate, and a great variety of articles. Symbol Ag (Argentum). Atomic weight 107.7. Specific gravity 10.5.

   Note: Silver was known under the name of luna to the ancients and also to the alchemists. Some of its compounds, as the halogen salts, are remarkable for the effect of light upon them, and are used in photography.

2. Coin made of silver; silver money.

3. Anything having the luster or appearance of silver.

4. The color of silver. Note: Silver is used in the formation of many compounds of obvious meaning; as, silver-armed, silver-bright, silver-buskined, silver-coated, silver-footed, silver-haired, silver-headed, silver-mantled, silver-plated, silver-slippered, silver-sounding, silver-studded, silver-tongued, silver-white. See Silver, a. Black silver (Min.), stephanite; -- called also brittle silver ore, or brittle silver glance. Fulminating silver. (Chem.)

   1. A black crystalline substance, Ag2O.(NH3)2, obtained by dissolving silver oxide in aqua ammonia. When dry it explodes violently on the slightest percussion.

   2. Silver fulminate, a white crystalline substance, Ag2C2N2O2, obtained by adding alcohol to a solution of silver nitrate; -- also called fulminate of silver. When dry it is violently explosive.

      German silver. (Chem.) See under German.

      Gray silver. (Min.) See Freieslebenite.

      Horn silver. (Min.) See Cerargyrite.

      King's silver. (O. Eng. Law) See Postfine.

      Red silver, or Ruby silver. (Min.) See Proustite, and Pyrargyrite.

      Silver beater, one who beats silver into silver leaf or silver foil.

      Silver glance, or Vitreous silver. (Min.) See Argentine.

n. Any of several explosive compounds of silver

Fulminating silver is an historic name which may apply to a number of silver based explosives which "fulminate" or detonate easily and violently. It has no exact chemical or dictionary definition, however it may refer to:

• silver fulminate (which, confusingly, is the only "fulminating silver" to be a silver compound with the fulminate anion)
• silver azide, AgN
• a mixture, a decomposition product of Tollens' reagent
• silver nitride, AgN - one of the earliest silver based explosives
• the alchemical substance "Argentum Fulminans"

The stability of many of these compounds can vary depending on how they are stored or handled, with levels of hydration often being a major factor.