This collection features three rock specimens, two of which are pure Granite and one is a combination of Granite with other minerals, all displayed on reddish-brown wooden presentation bases. Granite is an intrusive igneous rock formed from the cooling of magma beneath the Earth’s surface, known for its coarse crystalline texture and speckled mineral composition.
The first specimen (left) is a piece of Granite with a somewhat rough surface, yellowish-brown to cream in color, exhibiting a clear granular texture. Its shape is irregular and shows signs of natural weathering. The second specimen (center) is particularly striking as it is a large chunk predominantly composed of milky white Quartz crystals, interspersed with sections showing a pale purple or lavender hue, likely Amethyst or another Quartz variety. This indicates it is Granite with significant Quartz and Amethyst mineral inclusions.
The third specimen (right) is a darker piece of Granite, brownish-grey in color, with a denser and more uniform granular texture compared to the first specimen. Its surface is more consistent and displays the typical mineral composition of Granite. The first specimen originates from Sitiung, Sawahlunto/Sijunjung Regency. The second specimen is from Sumpur, specifically from Sawahlunto/Sijunjung Regency. Meanwhile, the third specimen comes from Padang Pariaman Regency. The presence of granite in these areas underscores West Sumatra’s geological richness with its extensive igneous rock formations.