SIDIKALANG, GAJAHTOBANEWS.COM – Sedimentary Exhalative Zinc-Lead Deposits in Indonesia, located in Dairi Regency, North Sumatra Province is one of the highest grades in the world. Those deposit is located near Sopokomil, Silima Pungga-Pungga district which will be exploited by one of the private business entities.

 

 

According to previous research conducted by the business entity, there are several locations in Dairi Regency and its surroundings that have SEDEX deposits such as Sinar Pagi Village located in Tanah Pinem District, Lubuk Raya Village located in Gunung Sitember District, and Buluh Laga Village located in Juhar District in Karo Regency. According to the study, it seems that SEDEX deposits have never been found even indications of metal mineralization in Dolok Siraut.

 

Read Kuta Buluh  Copper - Gold bearing outcrop news

https://www.gajahtobanews.com/editorial/lipus/new-copper-and-gold-bearing-zone-found-in-kuta-buluh-village-dairi-regency-north-sumatera

 

Contour map of Dolok Siraut.

 

Dolok Siraut is an area consisting of several limestone hills, with crystalline limestone as the main constituent. Dolok Siraut area has a distance of about 10 km from the location of SEDEX Sopokomil deposits, administratively located in Siempat Nempu District bordering Lae Parira District and Siempat Nempu Hilir District. Limestone mining activities in this area have been carried out 50 years ago, which supplies the limestone needs of North Sumatra and other provinces.

 

Massive sulphide outcrop with high grade metal content in Juma Teguh Village.

 

Based on information from the surrounding residents (Juma Teguh villagers), Dolok Siraut has actually explored but they have found nothing. They said that when foreign nationals built about 3 exploration monuments at the top of Dolok Siraut. The information we obtained when we showed them the discovery of pyrite metal minerals.

 

 

The metal mineral that we found in Juma Teguh Village is in black shale, which is among the crystalline limestone. The mineral has a dominant feature of pale yellow with metallic luster, black streak color, difficult to scratch by nails and calcite minerals (CaCO3), and density calculated about 4.8 gr / cm3, which we conclude as pyrite. But for impurity / metal impurities are difficult for us to identify. For additional information, the black shale outcrop has a very concentrated sulfur smell.

 

Massive sulphide outcrop with high grade metal content in Juma Teguh Village.

 

The metal mineral is seen piling up on the coating of black shale so we concluded that stratiform structure (forming strata) is a type of structure that corresponds to the appearance of the mineral. In the coating of these metal minerals can sometimes be seen pyrite with a framboid structure (raspberry-shaped) of varying sizes.

 

  

 

 

    

 

 

The presence of high grade pyrite dan metal minerals outcrop in Juma Teguh Village proves that Dolok Siraut has the potential of SEDEX metal deposits, but still requires exploration activities to find the presence of economical mineral ores such as zinc and lead ore (Sphalerite and Galena) which are usually found in SEDEX deposit types. We hope that this area becomes a target of research, especially in the field of mineralization so that information about metal mineralization on the island of Sumatra is more complete. (019/Frederic Steven)

 

You can acces the sample and outcrop images from the link available below:

https://drive.google.com/drive/folders/1-0Y2sa4eGJCX4gEjAishTGyBHqiCt-Ke?usp=sharing