Phu Lon

Terrain

General Condition

Phu Lon looks like a mountain or a hill. It consists of 2 hills:Phu Lon 1 in the north and Phu Lon 2 in the south. The mineral resource area is about 150-400 meters wide and about 660 meters long, covering an area of ​​approximately 0.2 square kilometers or about 125 rai (Department of Mineral Resources 2009).

The surrounding terrain is a steep mountainous area. interspersed with corrugated and sloping areas The north and east faces the Mekong River. There is a small natural stream. flows through the corrugated area or the area between the high mountains The general environment is deciduous dipterocarp forest, arable land. Cultivation of field crops and horticulture There are people's houses located along the road that cuts through the high mountains periodically. and set up as a dense community in Ban Muang Subdistrict in the southeast of Phu Lon Along the Mekong River

At present, Phu Lon is one of the important sources of iron, copper and gold in Nong Khai Province. Local villagers call the Phu Lon mine area the Peacock Cave, probably because the walls of the mine tunnels are green with copper ore. or the rust of copper decomposing from the original ore

Phu Lon in the area of ​​Wat Tham Khao Khiri Banphot Areas were reconditioned and various sanctuaries such as pavilions and cloisters were built. but retains most of the ancient mining tunnels The boulders on the hills and tunnel walls appeared green and brown of minerals evident throughout the hills. Mine tunnels are both small and large. Some of the larger tunnels are equipped with light bulbs and stairs for walking inside. Some of the smaller tunnels enshrine various Buddha images and idols. Some places are converted into places of introspection.

Height above mean sea level

Waterway

Mekong River

Geological conditions

From the report of the Department of Mineral Resources (2009), mentioning the geology of Phu Lon that The local rocks are Devonian shale, consisting of limestone shale, siltstone and chert, with limestone lens inserted in these strata. These strata are covered by Permo-Triassic volcanic rocks, including rhyolite, rhyolite tuff, andesite and volcanic pebbles. Subsequently, the local rock layers were intruded by Triassic igneous rocks in both stock and dike formations, consisting of diorite, monsodiorite, and sedimentary rock. Quartz monsonite, monsonite, and andesite. The effect of the intrusion of such igneous rocks resulting in a replacement transformation. (Metasomatism) in the area of ​​contact between local rock and intrusive igneous rock. Garnet, Scarn, Marble, Clack Silicate was born. and hornfels stones There are calcopyrite and pyrite crystals embedded in the rock garnet, scaran, and small strings of minerals. And it is a mineral wire in the form of a net (Stockwork) inserted in the rock at the contact area as well.

In addition, iron ore pods of magnetite type were also found. and quartz-calcite Infiltrated the latter with other opaque minerals. Commonly found in quartz-calcite chains include magnetite, sphalerite, hematite, marcasite, bornite, molybdenite and natural gold. Calcopyrite and Bornite are classified as primary copper minerals, which later decay to secondary copper minerals, comprising mostly malachite, green and azurite, blue in color. Local stones in the area of ​​contact As for gold ore, it is very small. cannot be seen with the naked eye It is found in the crystals and chains of calcopyrite that penetrate into the cracks of pyrite and garnet.

from the analysis of samples of sulfide minerals which consists of Calcopyrite and pyrite were found to contain copper 1.0-1.5%, gold 0.8-1.2 g/ton, and silver 4-5 g/ton, and their values ​​were lower in igneous rocks. and found that when one element was higher The remaining two elements will also have higher values. (Department of Mineral Resources 2009)

Archaeological Era

era/culture

Archaeological age

Scientific age

Types of archaeological sites

archaeological essence

Phu Lon Mine is probably the oldest copper mine in Thailand. Located on the Mekong River From past surveys, traces of mining activities have been found at several points. The remains of underground mines, chimneys, tunnels, and crushing grounds show traces of production from the process of digging, extracting, and smelting. There are also habitats and evidence of other types of mining tools, such as a mole pickaxe, crushed stone or pound. Crushed ores, crucibles, metal molds and bronze shards, etc.

Phu Lon contains iron ore, gold and copper, but is generally well known for its copper ore deposits. Because it has been made since ancient times. Characteristics of the ancient copper mine at Phu Lon is a ore to smelt the copper metal. There appeared to be several mining tunnels dug into the zone of copper ore. Some tunnels are about 5-7 meters wide and about 12 meters deep.

A study by Pigott and Suraphon Natapintu during 1984-1986 (Suraphon Natapintu 2007; Pigott 1985; Pigott and Natapintu 1988; Natapintu 1988) found that the shape of the tunnel from excavation There are two types of minerals, indicating at least two levels of mining techniques:

1. Early mining Use tools, or “bulls,” made of large river pebbles. The tunnel from the mining is therefore quite round. The walls are quite smooth. From the exploration and excavation discovered large gravel stones with traces of use in the form of smashing or smashing until cracking at both ends a lot. by encountering common in the strata of rubble from mining The pebbles were probably taken from the Mekong River.

2. Recent Copper Mining Presumably, metal tools were used. making tunnels from mining narrow long, rambling in many directions The walls of the tunnels are angular, angular, and in some tunnels there are still deep grooves similar to the chisel tool marks. This makes it presumed to be a trace of iron tools used in mining.

In addition, the study found areas with traces of mineral preparation and dressing known as "Pottery Flat" age determination from charcoal samples obtained from excavations in this area. Combined with the study of soil layers formed by deposition of rocks and minerals more than 10 meters thick from mining activities. causing the students to interpret that the first copper mining activities at Phu Lon May occur at least 2,000 BC, or about 4,000 years ago, since the beginning of the use of bronze in the northeast of Thailand. and continued until about the second half of the 1st millennium BC (Suraphon Nathapindu 2007).

Excavations at Phu Lon also found evidence of bronze casting in this area, namely crucible/smelting scraps and bronze scraps, Professor William Vernon, one of the Working Group on Ancient Metallurgy Projects. have studied clay crucibles from excavations in the area "Centerpiece yard" which is on the northeastern slope of Phu Lon. Found that the metal fragments trapped inside of the crucible were natural copper, tin-bronze and tin metal, indicating that copper production at Phu Lon was related to bronze production And Phu Lon miners have access to or obtained tin for bronze production (Suraphon Nathapindu 2007). They also have knowledge of tin metal and bronze production.

The assumption that the chimney and tunnel mining at Phu Lon instead of the open-pit mining is an open-pit mine like the Hab-Map mine. There are many concepts, for example, the Phu Lon people in the past did not have enough knowledge and experience in irrigation for open-mining. The open-top mining was much larger than the excavation work to become an underground mine as it is today. The Phu Lon people in the past may have been more proficient or familiar with underground mining techniques such as craters and tunnels. Underground mining technology is similar to Indian or Middle Eastern mining, as was tin mining on Thalang Island and Takua in ancient times before China entered open-pit mining.