Exotic sediment

Purchase Price Typical purchase prices, including drive motors, of tubular and disk sedimenting centrifuges are given in Table 18-16. The price will vary upward with the use of more exotic materials of construc tion, the need for explosion-proof elec trical gear, the type of enclosure required for vapor containment, and the degree of portability, and this holds for all types of centrifuges. 

Amari, S., Ozima, M. (1985) Search for the origin of exotic helium in deep-sea sediments. Nature, 317, 520-2. 

An anthropogenic impact on metals in coastal marine sediments has been demonstrated repeatedly. Lead has been shown to be enriched in coastal sediments. Even more exotic elements such as silver (photography) and osmium (electron microscopy) are enriched in the sewage of some cities and can be traced from their source. 

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