Eclogite is formed when igneous or metamorphic rocks that contain significant amounts of mafic minerals are exposed to pressures that exceed 1.5 gigapascals and high temperatures. Though chemically similar to basalt, the appearance of eclogite is quite distinct, being significantly more colorful than many other types of rocks. Thus, the coarse- to medium-grained green and red (sometimes pink) mineral matter is relatively easy to identify, even to those with an untrained eye. Typically present on Earth in small blocks or bodies, some of the best-known occurrences of eclogite are found in California, Norway, South Africa, Scotland, and the Alps.
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