International Journal of Mining and Mineral Engineering (4 papers in press)

Regular Issues

• An advanced overview of recent developments in tantalum, tin, and tungsten production in Rwanda  
  by Philemon Lindagato, Yongjun Li, Gaoxue Yang, Machá?ek Jan 
  Abstract: With the proliferation of advancements in high-tech devices, the availability and sustainable supply of tantalum, tin, and tungsten (3T) as raw materials may play a crucial role. There have been controversial arguments about the origin of Rwandan 3Ts. The authors believe that it is necessary to investigate their origins by concentrating on the geology, mining, and reforms that drive 3T massive production. The findings revealed that Rwanda became the world’s largest tantalum producer with 51% between 2011 and 2015, and has remained in the top three worldwide producers since 2008. The exploitation of an abundance of rock-bearing 3T mineral deposits, mining sector reforms, and the successful implementation of supply chain regulations are primarily attributed to this expansion. Their consistent output is thought to be linked to the privatisation of the mining sector, which brought about modernization and industrialization, which contributed in the formalisation of artisanal and small-scale mining (ASM).
  Keywords: Tantalum; Tungsten; 3T; Artisanal and small-scale mining (ASM); Mineral; Mineral traceability; Great Lake Region (GLR); Coltan; Mining; Cassiterite; SMART.
  DOI: 10.1504/IJMME.2023.10055080
   
  
• 3D-imaging of boulders using a solid-state 2D profilometer: case study for autonomous robotic rock breaker  
  by Ilpo Niskanen, Santeri Lampinen, Matti Immonen, Lauri Hallman, Martti Mikkonen, Jarno Karvonen, Juha Kostamovaara, Jouni Mattila, Rauno Heikkilä 
  Abstract: Measurements of a boulders fundamental physical properties like volume and shape can offer valuable insights for secondary breaking of boulders by a robotic rock breaker. This study analysed boulder shapes using a pulsed time-of-flight (TOF) solid-state laser profilometer. The 3D surface of boulders was reconstructed creating triangular meshes from point clouds provided by the profilometer. The main advantages of the 2D profilometer are the good measurement precision and accuracy, high speed, small size, real-time measurement capability, low weight, eye-safety, and lack of moving parts. The results indicate that a 3D map facilitates boulder diagnostics, aids in decision making, and represents a step towards a fully integrated autonomous robotic rock breaker in the mining industry. The present procedure is not only restricted to boulders, but it has also potential for other targets in industries that require precise determination of shapes for decision making.
  Keywords: time-of-flight (TOF) profilometer; stereo vision camera; boulder; robotic rock breaker; point cloud; shape.
  
  
• EFFECT OF SEASONAL VARIATIONS ON QUARRY OPERATIONS IN SOUTHWEST NIGERIA  
  by Thomas Busuyi Afeni, Babatunde Adebayo, Abraham Ogundayo 
  Abstract: A study to assess the effect of seasons on quarry operations and productivity in South-Western, Nigeria was carried out. Data were collected through oral interview, supplemented with the use of well-structured pre-tested questionnaires to achieve the aim of the study. The findings show that seasonal changes have effect on drilling, blasting, and crushing operations carried out in the quarries. The results revealed that aggregate production was higher during the dry season across all the quarries with Samchaze quarry having the highest production of 5446064,000 tons attributing to reduced downtime from rainfall and higher aggregate demand due to increased engineering projects rate in the dry season. With regards to sales, the findings showed a decrease in aggregate sales in the wet season in all the quarries with Western quarry making the lowest sales of 2,7006,000 tons while Samchaze quarry made the highest sales of 11,00015,000 tons. Health challenges like respiratory infections and heat stress were greater in the dry season while common cold, malaria and typhoid, cough and catarrh were common during the wet season. Eye infections, chest and hearing problems were felt in all the seasons. Appropriate recommendations were made to mitigate these seasonal changes impacts.
  Keywords: quarry; seasonal variation; drilling; blasting; crushing and productivity.
  DOI: 10.1504/IJMME.2023.10056431
   
  
• Mineralogical Studies of Cretaceous Phosphatic Nodules of Nambakuruchi Block of Tiruchirappalli District, Tamil Nadu, India  
  by Ajhar Hussain, K. Farahim Khan, Firoz Ahmad 
  Abstract: The Cretaceous phosphatic nodules of study area are found in different sizes and shapes. Elliptical, cylindrical, globular, conical and irregular, with veins containing calcite, gypsum and celestite and minor amount of the montetrisaite are the common shapes. The thin section, X-ray diffraction and scanning electron microscope (SEM) studies show that the carbonate fluorapatite (CFA) is the main phosphate mineral of apatite family. Minerals like calcite, quartz, feldspar, kaolinite, chlorite, montimorlinite are the minor constituents. The crystal of the phosphate is brown to grey colour with bryozoan fragments. The fine phosphatic grains of nodules with silt size are embedded in fine matrix. Fragments of the fossils and others small carbonate particles show light to dark lamination. Coated grains, peloids, and fine detrital grains are found in these nodules. The shape of the peloids is rounded and having no well-defined structure which indicates fluctuating/or high energy environmental conditions. Micro cracks with microbial mat are also common with algal structure. Presence of organic matter, calcite, quartz and feldspar minerals is strongly supporting oxic to suboxic environmental conditions.
  Keywords: phosphatic nodules; Cretaceous; Nambakuruchi; carbonate fluorapatite; CFA; mineralogy; India.
  DOI: 10.1504/IJMME.2023.10056435