Because it is hard and has a smooth texture, andesite has been used in the past for various human needs, ranging from household tools and constructions such as spice grinding stones, mortar, baseboards, floors, to matters related to religion, especially for the construction of temples (such as temples on the island of Java). In my area, a large number of ancient tombstones were manufactured from andesite.
As you know, this aphanitic (fine-grained) igneous rock is an extrusive volcanic rock, so it is commonly found in volcanic areas and also in rivers due to erosion in volcanic areas which are then transported by water (known as epiclastic rock). With the availability of natural resources, it is quite understandable then how many ancient cultural products made of andesite can be found in an area like mine in Aceh. But what then becomes the question in my mind is how exactly did the ancient people mine andesite either from mountainous or hilly areas or from rivers?
Starting from a toponymy that confused me in Lhokseumawe, Aceh, I finally flew across the Malacca Strait to the neighboring country, Malaysia. The reason is because in my city there is a sub-district called Batuphat which explicitly means "Batu Pahat" in Malay, which means carved stone. However, in the sub-district, which has hilly topography, there has never been found any ancient objects or structures that could explain the reason for its naming as carved stone. Meanwhile, in the Bujang valley which is situated in Kedah, Malaysia, an ancient temple was known as the Bukit Batu Pahat temple, which means the carved stone hill. That is my reason for choosing the Bujang valley, near Merbok, Kedah, as one of the destinations in my visit to the neighboring country. That is to find out whether the similarity of names can reveal something I do not know about a sub-district in my country which in essence also has its history in ancient times.
The Bujang Valley is an archaeological area located between Mount Jerai in the north and Sungai Muda in the south. Bukit Batu Pahat Temple or also known as Lembah Bujang Temple is a Hindu temple which is the main ancient building in the area.
A very rich museum with various archaeological collections is also there, and this is a model of the landscape of the Bujang valley and its surroundings contained in the museum.
Indian-infuenced achitecture and artefact finds in Kedah.
After walking to several parts of the area, I was very interested when I saw a river to the left of the temple building. It is the Merbok river.
The next time, I saw the columns that had been locked up in a section of the river and also on the banks. In the columns, I saw trimmed blocks of andesite rock as well as some that had not been completely trimmed from their original location.
The writing on the board next to me said: These history sites are located at Bukit Batu Pahat, side of Merbok River. The artefacts of carved stones are for "Candi" building. These carved stones of door beam, column and stone hole hole are believed made in 11-12 Century.
That part really caught my attention because I thought it would answer or shed some light on how ancient people actually mined andesite. Although I cannot understand much more about the mining process I can observe shallow holes lined up in a straight line which I can confirm is the result of erosion of the water. They create a kind of artificial erosion by dripping water on a rock body which is taken for them to use as a base for the various cultural objects that they will produce.
That I think is very careful work, and because it does not destroy the other parts as if using explosives, I think that method is very friendly to nature, although perhaps have to be patient and wait until the artificial erosion has actually allowed the andesite rock to be trimmed.
A yoni on display in the site area.
A large container made of andesite material.
And a lot of baseboards.
At this point, I think my trip and visit to the site has given me a little insight into how those ancient people mined andesite which they then used to produce various cultural objects of their time.
There was a little relief after I got home from there, but yes, there are still many other questions that still confuse me!😜
All the pictures here are from my personal files.