Looking at the Rock Cycle Through Pottery. Review Questions:. What is a rock? What is a mineral? How do igneous rocks form? How do sedimentary rocks form? How do metamorphic rocks form?. Mineral Soil Types. What is sand? Made primarily of quartz (SiO2)
Made primarily of quartz (SiO2)
Defined by a relatively LARGE particle size of 2mm-0.062mm
Defined by a MEDIUM particle size 0.062mm-0.0039mm
Particle size is SMALL; less than 0.0039mm
Most clay is made of silicon tetrahedrons that are glued together with Fe, Na, K or water
Outer layer has a negative net charge; thus attracts a lot of positive cations like K and N
If a grain of sand were the size of a basketball, then a piece of silt would be the size of a marble, and a particle of clay would be a pinpoint. Clay particles are tiny, less than one 12,500th of an inch.
Behind the Pottery
A clay filled tobacco field
10 miles from the Jones Pottery
How can we answer this question? What information do we need?
Top temperature of the kiln is 1260° C (2300° F)
Partial melting begins at 800° C (1472° F)
The clay particles that are fired undergo a metamorphism. Under intense heat, they partially melt and form something else altogether.
Glazes that are painted on the pot completely melt. They are made largely of glass, so they are lowest on Bowen’s Reaction series and melt most easily.