Iraqi Geological Journal Awad and Awadh 2021, 54 (1A), 11-22 Iraqi Geological Journal Journal homepage: https://www.igj-iraq.org DOI: 10.46717/igj.54.1A.2Ms-2021-01-23 11 Manufacturing Perforated and Ordinary Bricks Using Injana Claystone Exposed in The Middle of Iraq Ali Mutlag Awad 1 and Salih Muhammad Awadh 1, * 1 Department of Geology, College of Science, University of Baghdad, Baghdad, Iraq * Correspondence: salihauad2000@yahoo.com Received: 26 October 2020; Accepted: 17 November 2020; Published: 31 January 2021 Abstract This study aims to use claystone beds exposed in the Injana Formation (Late Miocene) at Karbala-Najaf plateau, middle of Iraq for the manufacturing of perforated and ordinary bricks. The claystone samples were assessed as an alternative material of the recent sediments, which are preferred to remain as agricultural land. The claystones are sandy mud composing of 29.1 - 39.1% clay, 37.2 - 54.8% silt and 14.1-26.8% sand. They consist of kaolinite, illite, chlorite, palygorskite, and montmorillonite with a lot of quartz, calcite, dolomite, gypsum and feldspar. Claystone samples were characterized by linear shrinkage 0.01 - 0.1%, volume shrinkage 0.1 - 0.9%, bulk density 1.2 - 2.11gm/cm 3 (1.68 g / cm 3 average), and the efflorescence is varied from low to nil. The claystones are accordingly considered as a suitable material for the manufacture of perforated and ordinary bricks in grades A and B based on Iraqi Standard specifications No. 25 (ISS, 1993). Keywords: Perforated brick; Ordinary brick; Injana claystone; Grain size; Brick color 1. Introduction Clays have historically been used to make bricks and other construction materials as they are the main raw materials that are invested in the manufacture of bricks (Merza and Faraj, 2017). Brick is currently produced in Iraq from the recent clay which is a high-quality soil that can be used for agriculture. This study is therefore seeking to find an instead material than the agricultural soil to be provided to the brick factories. The claystone beds in different formations (Al- Mukdadiya, Fat'ha, Gercus, Euphrates and Injana formations) in Iraq were evaluated for manufacturing of cement and ceramic by several researchers; for instance. Awadh and Al-Owaidi (2020) used the marl of Euphrates Formation to produce a high-quality Portland cement in the middle of Iraq. Lateef (1976); Al-hakim (1998); Merza and Mohyaldin (2005); Maala, et al. (2007) have mentioned that claystones fit to the Iraqi standard specifications (ISS) for bricks industry. Therefore, the exposed claystone beds of the Injana Formation (Late Miocene) in the study area were geologically assessed for the brick industry. The aim of this study is to evaluate claystone of the Injana Formation in the Karbala-Najaf plateau in the middle of Iraq for the manufacturing of the ordinary bricks (OB) and perforated bricks (PB). 2. Study Area and Lithostratigraphy The study area is located in the Karbala-Najaf plateau along two cliffs known locally as Tar Al- Sayyed and Tar Al-Najaf in central Iraq (Fig. 1). The Injana Formation (Late Miocene) is exposed along both Tars and in many small adjacent isolated hills. The sequences of exposed rocks in the study area were represented from oldest to youngest as follows: Euphrates, Fat'ha, Injana and Dibdibba