Clay resources

One of the more obvious examples of this interaction involves the addition of temper to a clay matrix (temper may be another clay, but is more often a nonplastic material). The effect of tempering varies a relatively pure material, such as quartz, may reduce elemental concentrations in a ceramic paste by a constant proportion (49). Addition of other kinds of temper or clay will result in a complex relationship of dilution and enrichment (14, 25, 50). Because elemental concentrations in sediments vary depending upon grain size (e.g., references 51-53), the size distributions of the added nonplastics also contribute to compositional complexity. If behavioral inferences are to be drawn, the culturally induced elemental variation arising from texture and temper differences among pottery produced from a single clay resource requires more than simple grouping and summary statistics. 

Potters in northern Arizona have been known to individually exploit personal clay resources from either the marine Mancos shale or the volcanic Chinle formation, resulting in different compositions for pots made in the same village, while potters in New Mexico can likewise exploit the same widespread Mancos and Chinle clays. Thus pots made in Arizona could chemically resemble pots made in New Mexico more than they resemble other local pots. 

Oudemans, F.M., J.J. Boon, R.E. Botto. 2007. Clay resources and technical choices for Neolithic pottery (Chalain, Jura, France) chemical, mineralogical and grain-size analyses. Archaeometry 49 23-52. 

S Fig. 2. Map of Mayan archaeological sites and clay resources of the Palenque region, Chiapas and Tabasco, Mexico Solid triangles are archaeological sites. Numbers refer to compositionally distinct day resource zones... 

Resources for Potash Fertilizers. Potassium is the seventh most abundant element in the earth s cmst. The raw materials from which postash fertilizer is derived are principally bedded marine evaporite deposits, but other sources include surface and subsurface brines. Both underground and solution mining are used to recover evaporite deposits, and fractional crystallization (qv) is used for the brines. The potassium salts of marine evaporite deposits occur in beds in intervals of haUte [14762-51-7] NaCl, which also contains bedded anhydrite [7778-18-9], CaSO, and clay or shale. The K O content of such deposits varies widely (see Potassium compounds). 

Demonstrated reserve quantities are estabUshed by measurements including drillings surface sampling, etc. Inferred reserves are those derived from geological survey information, not by measurement of the extent of the particular reserve. Not included herein are identified marginal and speculative resources, such as the oil-field and geothermal brines and lithium-hearing clays. These latter reserves are speculative as to extent, not existence. Total undiscovered clays in the western United States are speculatively estimated at 15 x 10 t lithium (16). More detailed Hsts of reserves are also available (15,17). 

Lignite. Deposits generally classified as unconventional uranium resources occur in lignite and in clay or sandstone immediately adjacent to lignite. Examples are uraniferous deposits in the Serres Basin, Greece, North and South Dakota in the United States, and Melovoe in the CIS (17) (see... 

Another important consideration pertains to the metal content of the deposit. A deposit with a content of iron of about 20% can have little value as an iron ore since there are several deposits with 30-50% iron. Earlier, a copper ore with a minimum of 5% copper was regarded or accepted as a copper ore. However, today, thanks to advancements in technology, rocks with as little as 0.5% copper are mined and processed economically despite the fact that the price of copper, in comparison with those of some other metals, might be showing a downward trend. It is possible that in the future, other resources, which are not considered to be worth exploiting today (such as the manganese nodules or the clays), would become acceptable ores for manganese, copper, nickel, cobalt, and aluminum. 

U.S. EPA, Design, Construction, and Evaluation of Clay Liners for Waste Management Facilities, Technical Resource Document, Report No. EPAJ530/SW-86/007, U.S. Environmental Protection Agency, NTIS Order No. PB86-184496/AS, Cincinnati, OH, 1986. 

Chou, S.-F.J. and Griffin, R.A. Soil, clay and caustic soda effects on solubility, sorption and mobility of hexachlorocyc-lopentadiene. Environmental Geology Notes 104, Illinois Department of Energy and Natural Resources, 1983, 54 p. 

More generally, Walter et al. (2002) tested the spatial cross-correlation between weed species and several soil properties. Certain weeds were correlated with specific soil chemical properties (e.g. P, pH) however, other species did not show consistent correlation with soil types between fields and sampling times, and some were correlated with more than one soil property. The most consistent relationship was between weed density and clay content. This result suggests that weeds have different resource requirements and that modifying soil conditions to manage certain weeds may promote others. 

Bader, S. (2003) Modelling of chemical osmosis across clay membranes comparison with experiments, submitted to Advances in Water Resources... 

Brindley, G. W., In Clays and the Resource Geologist Longstaffe, F. J., Ed. Mineralogical Association of Canada Toronto, Canada, 1981 Chapter 1. 

Limestone is an important mineral resource. One use is in the making of cement. Cement is made by heating clay with crushed limestone. During this process, the calcium carbonate is first converted to calcium oxide. 

Note that the manufacture of A1 occurs from plentifully available natural resources at present this is bauxite and eventually it will be clay. The electricity for many aluminum plants comes from hydroelectric plants, so that the use of mechanically rechargeable A1 batteries (obtained in this manner) would lead to a reduction in greenhouse gases faster than that of re-forming methanol on-board cars to obtain hydrogen for fuel cells (because this gives rise to C02). (Bockris)... 

TUB-49 — U.S. origin. Collected in South Dakota (Clay County), from roadside ditch in 1982. Available (accession Ames 2729) from USDA, ARS, National Genetic Resources System, NCRPIS, Ames, IA 50011, U.S. 

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