A gem can be defined as a mineral that occurs naturally and is crystalline enough to be cut and polished.
The first quality is its beauty which is highly dependent on the visual quality of a gemstone. The second is its durability. This quality is highly dependent on the hardness of a gemstone or the strength of its hardness. Generally, the higher the hardness value, the higher its durability. The third quality of a gemstone is its rarity, which is also very important.
As far as the history of universal gems is concerned, it spans from 25,000 to 3,400 years. Many scholars are of the opinion that the development of this industry started in this era. At present, Colombia, Africa, Madagascar, Sri Lanka, Myanmar, and Australia are the main countries in terms of gem deposits and the gem industry.
At present, the gem industry is popular in a significant number of countries. Considering the current state of this industry, about 200 types of minerals have been identified as gems in the world, of which about 75 types are found in Sri Lanka. Sri Lanka exports gems to about 50 countries, among which America, Japan, Hong Kong, Thailand, Germany, France, England, and Switzerland occupy an important place. Sri Lanka’s gem industry basically consists of three sectors: mining, polishing, and trading.
Despite being a hugely profitable industry, there are also a a significant environmental impact associated with mining. to natural vegetation cover, damage to plantations and fields, impact on land due to soil erosion, damage to man-made structures, and effects such as damage to health.
Damage to plantations and paddies and soil erosion to natural vegetation cover have a direct impact on natural vegetation cover due to the early removal of vegetation during the prospecting process in areas where gems are expected to be found.
Removal of vegetation cover
Intensification of soil erosion during the rainy season through the removal of vegetation cover is an adverse environmental impact caused by the mining industry.
Wasteland is suitable for mining. During mining, paddy fields or other crops are directly damaged in those areas, and the barren soil thrown out from the mines mixes with the fertile soil on the surface, changing the soil characteristics and lowering the quality of the soil.
Large pits and piles of earth caused by the impact on the ground and geomorphologic changes caused by gem mining are common in gem mining areas. Various constructions and buildings are damaged by digging under roads, houses, irrigation channels and culverts.
More care should be taken in construction-related mining, as the ground can be subject to subsidence due to doona mining.
After the mining is done, due to the non-closure of the mines, disease vectors such as mosquitoes are spread. A major health problem associated with this industry is the transmission of malaria by mosquitoes breeding in abandoned mines.
The water collected in these mine pits also causes a foul smell in the environment. Another problem that comes with it is the risk of mammals, reptiles, and even humans falling into unfilled mine shafts.
Collapse of riverbanks
Damage to streams and riverbanks is caused by the destruction of vegetation on the riverbanks, and as a result, the riverbanks collapse.
Heavy machinery used to dig the riverbed has caused this situation to arise. Another unintended consequence of river bed dredging is the loss of biodiversity that is unique to the organisms living in freshwater riparian systems. Unsuitable changes in their habitats under changing environmental conditions pose a great threat to the survival of some sensitive species.
Damping rivers results in the release of large amounts of sediment particles into the water through siltation and bank erosion. Due to the increase in sediment particles, the increase in water turbidity and the decrease in light transmission have a negative effect on the aquatic biodiversity of the system.
Decreasing light transmittance leads to the inactivation of food connections in rivers and streams by impairing the process of photosynthesis. Also, most of the fish species found in the streams and rivers of Sri Lanka are species that have adapted to live in clean water, and when the concentration of floating particles in the water increases, the blockage of their water bodies poses a threat to their survival. Due to the increase in the amount of soil particles entering the water in various ways due to mining, the problem of silt deposition due to forest clearing, cultivation activities, etc.
An important industry
Water pollution is also a major environmental impact due to gem mining. When the amount of silt increases, the water that could have been used as drinking water is limited.
Water pollution also occurs because the workers who temporarily settle in the gem mining areas do not have adequate sanitary facilities.
Gem mining is economically important to Sri Lanka because it is a major source of foreign exchange and also a source of employment for rural people. As such it is essential to take measures to reduce the damage to the environment due to mining activities.
The Central Environmental Officer has set up a separate department to provide advice on environmental problems arising during gem mining and to provide knowledge on the latest mining technology and how to use it to gem miners.
The following recommendations can be considered:
Prohibiting the use of heavy machinery for mining on land, allowing the river bed to be dug with spades only after careful consideration of the possible damage to the environment, monitoring the activities of refilling the mines and doona after the mining is completed, and illegal mining by the advisory authority a complete ban on dredging.
Prohibit horizontal pit mining in gem mines and mining areas without obtaining permits, to take measures to fill such pits at the end of mining if permitted, and to provide up-to-date instructions to miners.
The writer is following a Postgraduate Diploma course in Economics, at the University of Kelaniya.
