- Jasper conglomerate
Jasper conglomerates are a distinct type of
glacial erratic collected mostly fromglacial drift. The conglomerates were derived from the North American region of theCanadian Shield that is present onSt. Joseph Island and north and northwest of theBruce Mines of northernOntario approximately a 65 km east ofSault Ste. Marie . This rock is derived from thePrecambrian Lorrain Formation, which contains rocks associated with Precambrian (2200-2400 Mya) glaciation and the jasper conglomerates are attributed to sand and pebbles derived by erosion from older rocks and redoposited as gravity flows in water. The red pebbles or cobbles in the conglomerate are fragments ofjasper orbanded iron formation . Later these materials were lithified to form conglomerates and transformed by heat and pressure to formquartzite conglomerates. The early British settlers in the Bruce Mines, called the jasper conglomerate “puddingstone”, because it looked like boiled suet pudding with cherries. The main use of the jasper conglomerate is for decorative purposes.ee also
*
Hertfordshire puddingstone
*Roxbury puddingstone
*Ornamental stone
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