scholarly journals The Borax Method of Gold Extraction for Small-Scale Miners

2012 ◽  
Vol 2 (3) ◽  
pp. 5-10 ◽  
Author(s):  
Peter W.U. Appel ◽  
Leoncio Na-Oy
Keyword(s):  
Heavy Metal ◽  
Melting Point ◽  
Scientific Research ◽  
The Philippines ◽  
Toxic Element ◽  
Heavy Mineral ◽  
Small Scale ◽  
Gold Extraction ◽  
Reducing Costs ◽  
Capture Rates

Background. More than ten million small-scale miners (SSM) worldwide use mercury to extract gold, releasing large amounts of the toxic element into the environment. Alternatives to mercury have been suggested over the years to little avail. A group of miners in the Philippines has demonstrated that borax, when used as a flux for smelting gold out of heavy mineral concentrates, is an effective and safer substitute for mercury. Objectives. To present a basic comparison of the mercury amalgamation and borax methods of gold extraction for SSM. Methods. Borax was added to milled ore to reduce the melting point of gold to a level accessible to SSM. The amount of gold captured, and the amount of mercury released into the environment, was compared to two common amalgamation methods: whole ore and heavy metal. Discussion. The borax method appears to capture more gold, as well as eliminate the use of mercury. It is also less expensive. It is important to stop the use of mercury amongst SSM. However, health and environmental arguments alone are not enough to convince miners to switch. The argument of improving gold-capture rates while reducing costs is more compelling, and may help propagate the technique among small-scale miners. Conclusions. Scientific research should continue in order to further establish the uses and limitations of the borax method.

scholarly journals Heavy Metals Accumulation in Surface Waters, Bottom Sediments and Aquatic Organisms in Lake Mainit, Philippines

2020 ◽  
Vol 79 ◽  
pp. 40-49
Author(s):  
Emalina L. Ebol ◽  
Carlos H. Donoso ◽  
Rex Bombet D. Saura ◽  
Rolit Joan C. Ferol ◽  
Juliet Ruth D. Mozar ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Heavy Metal Contamination ◽  
Aquatic Organisms ◽  
Speciation Analysis ◽  
The Philippines ◽  
Small Scale ◽  
Safe Limits ◽  
Trace Concentrations ◽  
Metal Monitoring

Lake Mainit is one of the largest lakes recognized as Key Biodiversity Areas (KBA) in the Philippines with rich fishery resources. However, the lake is at risk from heavy metal contamination due to inputs of industrial, agricultural effluents and small-scale mining activities. The present work evaluated levels of heavy metals namely cadmium, lead, and mercury from key aquatic fauna and sediments from seven strategic sections of the lake in 2018. Muscle samples of all seven fish species assessed were below detections limits (BDL) for tHg and Cd. Trace concentrations of Pb in the muscles were detected in Oreochromis niloticus, Glossogobius giuris, Channa striata and Vivipara angularis but values were within safe ranges. Trace concentrations of Pb in the riverine crab (Sundathelpusa sp) exceeded safe limits. Both Cd and tHg were below detection limits in the three invertebrates assessed. Traces of Pb were detected in S4 (Magtiaco) and S5 (Jaliobong) below standard limits (0.05 ppm) only during the southwest (SW) monsoon but Pb were not detected across all stations during the NE monsoon of 2018. For Cd, however, trace concentrations were detected only during the NE monsoon wherein Cd in S2 (Mayag), S3 (Magpayang), S4 (Magtiaco), S5 (Jaliobong), S6 (Dinarawan) and S7 (Kalinawan) exceeded standard limits for Cd in waters (0.01 ppm). Concentrations of tHg in the water were not detected across the two sampling seasons in all seven tributary stations. In sediments, Pb were all detected during the southwest monsoon with highest Pb concentrations in S6 (Dinarawan) and S7 (Kalinawan) which exceeded safe limits. Trace Cd in sediments were mostly below detectable limits. Concentrations of tHg in sediments exceeded safe limits during the SE monsoon in S4 (Magtiaco) and S7 (Kalinawan) areas. These findings recommended that continuous heavy metal monitoring must be conducted. It is also strongly suggested to evaluate the presence of heavy metals in other aquatic organisms and assess the ecological risk posed by these heavy metals though heavy metal speciation analysis.

Thermal stability and heavy metal (As5+, Cu2+, Ni2+, Pb2+ and Zn2+) ions uptake of the natural zeolites from the Philippines

2019 ◽  
Vol 6 (8) ◽  
pp. 085204 ◽  
Author(s):  
Eleanor Olegario ◽  
Christian Mark Pelicano ◽  
Jenichi Clairvaux Felizco ◽  
Herman Mendoza
Keyword(s):  
Thermal Stability ◽  
Heavy Metal ◽  
The Philippines ◽  
Natural Zeolites

scholarly journals Accurate age estimation in small-scale societies

2017 ◽  
Vol 114 (31) ◽  
pp. 8205-8210 ◽  
Author(s):  
Yoan Diekmann ◽  
Daniel Smith ◽  
Pascale Gerbault ◽  
Mark Dyble ◽  
Abigail E. Page ◽  
...  
Keyword(s):  
Life History ◽  
Bayesian Approach ◽  
Age Estimation ◽  
Human Life ◽  
The Philippines ◽  
Monte Carlo Algorithm ◽  
Small Scale ◽  
Hunter Gatherers ◽  
Cultural Life ◽  
Ranking Order

Precise estimation of age is essential in evolutionary anthropology, especially to infer population age structures and understand the evolution of human life history diversity. However, in small-scale societies, such as hunter-gatherer populations, time is often not referred to in calendar years, and accurate age estimation remains a challenge. We address this issue by proposing a Bayesian approach that accounts for age uncertainty inherent to fieldwork data. We developed a Gibbs sampling Markov chain Monte Carlo algorithm that produces posterior distributions of ages for each individual, based on a ranking order of individuals from youngest to oldest and age ranges for each individual. We first validate our method on 65 Agta foragers from the Philippines with known ages, and show that our method generates age estimations that are superior to previously published regression-based approaches. We then use data on 587 Agta collected during recent fieldwork to demonstrate how multiple partial age ranks coming from multiple camps of hunter-gatherers can be integrated. Finally, we exemplify how the distributions generated by our method can be used to estimate important demographic parameters in small-scale societies: here, age-specific fertility patterns. Our flexible Bayesian approach will be especially useful to improve cross-cultural life history datasets for small-scale societies for which reliable age records are difficult to acquire.

scholarly journals Heavy Metals in the Soils of Placer Small-Scale Gold Mining Sites in Myanmar

2020 ◽  
Vol 10 (27) ◽  
pp. 200911
Author(s):  
Aung Zaw Tun ◽  
Pokkate Wongsasuluk ◽  
Wattasit Siriwong
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Gold Mining ◽  
Soil Samples ◽  
Small Scale ◽  
Mining Activities ◽  
Mining Operations ◽  
Metal Concentrations ◽  
Mining Sites ◽  
Heavy Metal Concentrations

Background. Artisanal and small-scale mining activities are widely practiced globally. Concentrations of heavy metals associated with gold, such as copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) can increase in the environment as a result of mining activities, leading to environmental pollution and pose toxicity risks to humans and animals. Objectives. The aim of the present study was to investigate soil concentrations of toxic heavy metals in placer small-scale gold mining operations in Myanmar. Methods. Soil samples were collected from three placer small-scale gold mining sites: Site A located in the Hmawbon public protected forest, Site B and Site C, situated in the Nant-Kyin reserved forest around Nar Nant Htun village. At each site, soil samples were collected from four gold mining stages (ore processing, sluicing, panning, and amalgamation). Atomic absorption spectroscopy was utilized to examine the concentrations of As, Cd, Pb, and Hg. Results. The highest heavy metal concentrations were generally found in the amalgamation stages across all the gold mining sites. Across the three mining sites, the maximum heavy metal concentrations in the amalgamation stage were 22.170 mg.kg−1 for As, 3.070 mg.kg−1 for Cd, 77.440 mg.kg−1 for Hg, and 210.000 mg.kg−1 for Pb. Conclusions. The present study examined the concentrations of As, Cd, Hg and Pb in the soil of several small-scale gold mining sites in Banmauk Township, Myanmar. The results demonstrated the presence of high concentrations of heavy metals in the soil of the gold mining sites. Miners in this area work without proper personal protective equipment, and frequent exposure to heavy metals in the soil may cause adverse health effects. The present study provides baseline data for future risk assessment studies of heavy metal contamination in gold mines. Competing Interests. The authors declare no competing financial interests

scholarly journals Sustainable Solutions for Oyster Shell Waste Recycling in Thailand and the Philippines

Recycling ◽  
2019 ◽  
Vol 4 (3) ◽  
pp. 35 ◽  
Author(s):  
Ramakrishna Chilakala ◽  
Chottitisupawong Thannaree ◽  
Eunsoo Justin Shin ◽  
Thriveni Thenepalli ◽  
Ji Whan Ahn
Keyword(s):  
Sustainable Management ◽  
Global Climate ◽  
Oyster Shell ◽  
Waste Recycling ◽  
The Philippines ◽  
Small Scale ◽  
Sustainable Solutions ◽  
Shell Waste ◽  
Waste Shell ◽  
Mollusk Shell

This paper studies the utilization and management of the waste mollusk shell. The two major export countries of mollusk shell are the Southeast Asia’s Thailand and the Philippines. First, the aquaculture of oysters and bivalve shells has been studied as background understanding. The effect of the global climate change on farming and the consequences of farming on the nearby environment and neighborhoods have also been discussed. The utilization technologies on the waste shell are available on a small scale and not industrialized. This study offers an enabling context under which a suitable method can take action to solve the overflow waste shell problem, and at the same time, provide sustainable management.

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