<p>Chlorite coats are believed to inhibit quartz cementation and preserve deeply-buried sandstone porosity. However, geologists face numerous challenges in evaluating the influences of chlorite coats in real cases. To tackle these challenges, this work reviewed a large number of case studies to discuss the proper way to evaluate their role using petrography. The following five main conclusions were drawn: (1) Compared to other coat parameters, coat coverage is more reliable in evaluating the influence of chlorite coats on quartz cements. (2) In addition to chlorite coats, quartz growth is influenced by multiple factors such as temperature, while sandstone porosity is affected by various factors including mechanical compaction; therefore, when evaluating the influence of chlorite coats, geologists should take these factors into account. (3) Even if no negative correlation exists between chlorite coats and quartz cements, and no positive correlation is observed between chlorite coats and sandstone porosity, one cannot simply conclude that chlorite coats do not inhibit quartz cements and protect sandstone porosity. (4) Chlorite coats can significantly occupy pore space, leading to a net porosity decrease. (5) Chlorite coats can undergo significantly dissolution, while whether this phenomenon is ubiquitous remains underexplored.</p>