How Do You Intimidate a Drug Dealer With Fulminated Mercury?
Fulminated mercury has the molecular formula Hg(CNO)2. It is a white power that explodes with the formation of mercury vapors in response to impact, friction, or heat.
Hg(CNO)2 → 2 CO + N2 + Hg
The explosive effects of mixtures of alcohol, nitrates, silver, and mercury were known even back in the days of the alchemists. Fulminated mercury was first described in 1800 by Edward Howard. Interestingly, investigations carried out by Liebig, Gay Lussac, and Wöhler on silver fulminate (AgCNO) and silver cyanate (AgOCN) led to the discovery of isomerism. Wöhler later recognized the structure of the fulminate anion (C=N–O). The crystalline structure of fulminated mercury was not explained until 2007 .
In the 19th century, fulminated mercury was used as an initiator for detonating dynamite. Due to its toxic nature and the difficulties in handling it, it was soon replaced by the safer lead azide. Walter therefore took a great risk when he marched into Tuco’s office with a kilo of unusually large and beautiful crystals and let Tuco play around with them. Put simply, it is practically a miracle that the substance did not explode before its dramaturgic role played out. Please do not try this at home!
 W. Beck, J. Evers, M. Göbel, G. Oehlinger, T. M. Klapötke, Z. Anorg. Allge. Chem. 2007, 633, 1417–1422. DOI: 10.1002/zaac.200700176