Amalgam (chemistry) gold") would not be extractable from ore using hydro-mechanical methods. Large amounts of mercury were used in "placer mining", where deposits composed largely of decomposed granite slurry were separated in long runs of "riffle boxes", with mercury dumped in at the head of the run. The amalgam formed is a heavy solid mass of dull gray color. (The use of mercury in 19th century placer mining in California, now prohibited, has caused extensive pollution problems in riverine and estuarine environments, ongoing to this day.) Sometimes substantial slugs of amalgam are found in downstream river and creek bottoms by amateur wet-suited
SAT Subject Test in Chemistry between the SAT Chemistry Test and the AP Chemistry exam, which is a more critical-thinking exam that is used not for college admissions but rather for college placement. Still, an AP course in Chemistry is sufficient preparation for the Chemistry SAT. The student is not allowed to use notes, textbooks, or a calculator on this test. The only resource a student may use is a periodic table which is provided with the test booklet. This table only provides atomic masses, atomic numbers, and symbols for each element. SAT Subject Test in Chemistry The SAT Subject Test in Chemistry is a