Gold Extraction Processes

Scientific American | October 31st, 1896

FROM very early times the ancients were attracted the beautiful color, the brilliant luster and the indestructibility of gold, and spared no pains in the endeavor to acqu

FROM very early times the ancients were attracted the beautiful color, the brilliant luster and the indestructibility of gold, and spared no pains in the endeavor to acquire it. In the code of Menes, who reigned in Egypt some 2,000 years before the time of Moses, the ratio of value between gold and silver is mentioned, one part of gold being declared equal in value to two and a half parts of silver, and it is, therefore, clear that the extraction of both metals from the deposits containing them must have been carried on before that time. It is indeed probable that gold was the first metal observed and collected, since it occurs in fragments of all sizes in loose sand, and the operations of collecting the larger pieces and melting them together are so simple. Among the rock carvings of Upper Egypt there are several illustrative of the art of washing auriferous sands by stirring and working them up by the hand in hollowed-out stone basins, and subsequently melting the gold in simple furnaces with the aid of mouth blowpipes. The earliest of these carvings is supposed to date back to about 2,500 B.C. However, in ancient times, gold appears to have been mainly derived from India, and that country continued to supply most of the gold used in Europe until the discovery of America by Columbus.

Gone with the flow

Bay Institute | August 1st, 2010

The Bay Institute's primer Gone with the Flow describes in plain language how runoff flowing from the mountain watersheds ringing California’s Central Valley provided c

The Bay Institute's primer Gone with the Flow describes in plain language how runoff flowing from the mountain watersheds ringing California’s Central Valley provided coldwater paradises for salmon returning to their native streams; turned lowland rivers and their floodplains into a rich source of food and shelter for young fish; mingled in the Delta’s complex maze of marshes and sloughs; and created a vast expanse of brackish water habitat essential for estuarine creatures in the upper reaches of San Francisco Bay. The primer also explains how the lack of access to most upland streams now forces migratory fish to cope with undesirable, often lethal flow conditions; how runoff in lowland rivers has been shifted from spring to summer, or even almost completely cut off in the San Joaquin basin, with disastrous consequences for the environment; how reverse flows in Delta channels kill hundreds of millions of aquatic organisms each year; and how the Bay is now in a permanent ecological drought because of the diversion of half its freshwater inflow.

Gone. Decades of greed, neglect, corruption, and bad politics led to last year’s Paradise fire, the worst in California history. It should never have happened. It will happen again.

California Sunday Magazine | July 31st, 2019

By the time I made it to Paradise, the deadliest wildfire in California history was four months past, and the burned-out ridge between the two river canyons was pouring

By the time I made it to Paradise, the deadliest wildfire in California history was four months past, and the burned-out ridge between the two river canyons was pouring rain. I was riding the Skyway, the road from Chico to Paradise, flatland to hilltop, trying to understand what forces had conspired last November to create a blaze of such anger that it took the lives of 85 people and destroyed 19,000 structures. I had puzzled out enough disasters to know that tragedy was a force of intricate construction. It wasn’t one detached act that materialized as tragedy but myriad smaller acts — some incidental, some accidental, others malevolent — that lined up in perfect continuity. Had one circumstance in the sequence lost its footing, a cosmic stumble, the next circumstance would have never hitched on, and tragedy would have been averted.

Good Samaritan Remediation of Abandoned Hardrock Mines Act of 2024

U.S. Government Publishing Office (GPO) | December 17th, 2024

To promote remediation of abandoned hardrock mines.

To promote remediation of abandoned hardrock mines.

Goodbye to “Rough Fish”: Paradigm Shift in the Conservation of Native Fishes

American Fisheries Society (AFS) | July 21st, 2021

Goodbye to “Rough Fish”: Paradigm Shift in the Conservation of Native Fishes

American Fisheries Society (AFS) | July 21st, 2021

While sometimes difficult to admit, perspectives of European and white males have overwhelmingly dominated fisheries science and management in the USA. This dynamic is ex

While sometimes difficult to admit, perspectives of European and white males have overwhelmingly dominated fisheries science and management in the USA. This dynamic is exemplified by bias against “rough fish”—a pejorative ascribing low-to-zero value for countless native fishes. One product of this bias is that biologists have ironically worked against conservation of diverse fishes for over a century, and these problems persist today. Nearly all U.S. states retain bag limits and other policies that are regressive and encourage overfishing and decline of native species. Multiple lines of evidence point towards the need for a paradigm shift. These include: (1) native species deliver critical ecosystem services; (2) little demonstration that native fish removals deliver intended benefits; (3) many native fishes are long-lived and vulnerable to overfishing and decline; and (4) fisher values and demographics shifting towards native fish conservation. Overall, existing native fish policies are unacceptable and run counter to the public trust doctrine where government agencies manage natural resources for public use. We encourage agencies to revisit their policies regarding native fishes and provide suggestions for developing more holistic, protective, and inclusive conservation policy.

Governing California Through Climate Change

Little Hoover Commission | July 1st, 2014

State government, which guided California through the instability of the Great Depression, managed the profound disruptions of World War II and steered, during following

State government, which guided California through the instability of the Great Depression, managed the profound disruptions of World War II and steered, during following decades, one of the nation’s great population, development and innovation booms, faces again an historic governing challenge in climate change. A $2 trillion annual economy and the needs of nearly 40 million residents ride on the outcome of the state’s preparations and response. Climate change, which most scientists believe has already begun, promises decades of wilder weather and great uncertainty regarding the scale of annual precipitation, wildfire activity, sea level rise and daily temperatures. These changes have powerful implications for agricultural production, air quality, real estate values, electricity generation, public health and California’s renowned quality of life.

Governing Nature: Bambi Law in a Wall-E World

Social Science Research Network (SSRN) | January 28th, 2021

Humanity has disrupted many of the fundamental processes that shape nature worldwide. Virtually no places remain unchanged. Many ecosystems have moved far from their hist

Humanity has disrupted many of the fundamental processes that shape nature worldwide. Virtually no places remain unchanged. Many ecosystems have moved far from their historic conditions and no longer support native species or traditional human uses. In the Anthropocene, a new geologic era dominated by the human impact on Earth, these problems will continue to get worse. In response, humans are intervening in ecosystems at a massive scale. This Article argues that, even as humanity engages in an unprecedented level of ecosystem management, existing environmental governance structures are ill suited to manage this new nature. Ecologists who focus on restoring ecosystems have begun to abandon efforts to recreate idealized historical ecosystems, recognizing that such efforts will fail. Instead, they embrace new approaches that acknowledge continuing human impacts and seek to shape impacted habitats in a way that benefits both human and other life. This Article examines the new ecological approaches, using their migration of purpose and approach to illuminate ecosystem management in the Anthropocene and the new obligations it places on environmental law. To sharpen this focus, the Article considers three case studies of managed ecosystems, detailing the extent to which humans are controlling nature. The case studies suggest that the existing literature seriously underestimates the magnitude of the questions society will soon face. The Article concludes that although we face the daunting prospect of reshaping the very fabric of nature, we lack the governance structures to decide what shape it should take. Society will need environmental law governance that can answer fundamental questions about humanity’s role in managing nature at all scales. This Article proposes several starting principles to encourage legal scholars to address this need.

Governor's Commission to Review California Water Rights Law Summary Final Report

State of California | December 1st, 1978

Governor's Commission to Review California Water Rights Law: Final Report

California State Water Resources Control Board (SWRCB) | December 22nd, 1978

The Final Report of the Governor's Commission to Review Water Rights Law, dated 12/22/1978.  The report contains the Commission's analysis of existing California water r

The Final Report of the Governor's Commission to Review Water Rights Law, dated 12/22/1978.  The report contains the Commission's analysis of existing California water rights law and recommendations for modifications. The Commission recommended 'modernization' in four areas:  water rights, efficiency in water use, instream uses of water, and groundwater.