Amalgam (chemistry) gold") would not be extractable from ore using hydro-mechanical methods. Large amounts of mercury were used in "placer mining", where deposits composed largely of decomposed granite slurry were separated in long runs of "riffle boxes", with mercury dumped in at the head of the run. The amalgam formed is a heavy solid mass of dull gray color. (The use of mercury in 19th century placer mining in California, now prohibited, has caused extensive pollution problems in riverine and estuarine environments, ongoing to this day.) Sometimes substantial slugs of amalgam are found in downstream river and creek bottoms by amateur wet-suited
What is Living and What is Dead in Indian Philosophy commenting on this point, notes: Hiriyanna expresses his perplexity in reviewing the Nyaya-Vaisesika view of consciousness, and then comes out with a comment equating this view with the Charvaka view of consciousness: What is Living and What is Dead in Indian Philosophy What is Living and What is Dead in Indian Philosophy is a 1976 book by Debiprasad Chattopadhyaya. Explaining the relationship between the soul and consciousness in the Nyaya-Vaisesika philosophy, Debiprasad Chattopadhyaya makes three points. First, consciousness in this view is knowledge (jnana) in an empirical sense. Second, consciousness is one of the multiple qualities of the soul. Third,