Built by a geologist

Rock Identification Quiz

GeoMiner's free rock identification quiz tests evidence-led reasoning across twelve questions without an account, timer, upload, or public leaderboard. Igneous questions cover visible and invisible crystal size, intrusive and extrusive pairs, glassy texture, vesicles, and composition limits. Sedimentary questions cover gravel, sand, silt, clay, clast rounding, fissility, carbonate evidence, and non-clastic materials. Metamorphic questions cover slaty, phyllitic, schistose, gneissic, granoblastic, hornfelsic, amphibolitic, and sheared fabrics. Cross-family questions test common look-alikes including shale versus slate, marble versus limestone, quartzite versus sandstone, and natural vesicles versus slag or weathering cavities. Each answered question provides an explanation and a direct route into the relevant source-backed guide or comparison. Answers and the current score stay in the browser; only the best numeric score is stored on the visitor's device. GeoMiner analytics receive only bounded actions, a broad score band, and an optional broad rock-family review group—never answer choices, question responses, specimen information, free text, photos, locations, or identifying data. The quiz is a learning tool rather than a competency certificate, professional assessment, or substitute for field and laboratory evidence.