Limestones<\/p>\n
I remember a shocking news story sometime ago about the
\nNational Museum in Jakarta concerning stolen paintings. The whole
\nstory was surprising indeed. But museums normally carry a lot of
\nwonders and curiosities, and some big surprises as well.<\/p>\n
I visited the National Museum last year for the first time. I
\nwas surprised to see some fossil corals in black limestone
\ncovering the museum's floor. The corals were Michelinia,
\nRaphrentites and Cyathaxonia of Early Carboniferous age (some 330
\nmillion years ago). Corals are whitish gray in color, and are
\nembedded in the black limestone known as marbre noir in Western
\nEurope. This type of limestone has long been quarried in Tournia,
\nwest Belgium, and used widely in Europe, together with petit
\ngranite, also from the same place. In Brussels, the capital of
\nBelgium and center of the EU, you will see these limestones in
\nabundance because they are used for road pavement. I happened to
\nknow this because I once lived in Belgium.<\/p>\n
Presumably, when the National Museum was constructed, some
\nbuilding materials were shipped from the Netherlands to Jakarta
\n(then Batavia). We can tell this because the characteristic
\nfeatures of rocks are often so prominent as to indicate their
\norigin.<\/p>\n
In the Museum of Geology in Bandung where I work, walls and
\npillars are covered by panels of gray limestone which, I was
\ntold, came from Padalarang, west of Bandung. The limestone is
\nknown as Radjamandala limestone among geologists, and is Late
\nOligocene to Miocene in age (about 25 million years ago).<\/p>\n
Quarrying operations in Padalarang are rather extensive.
\nLimestones are used for making lime, of course, and for
\nornamental stones such as \"marble\". In a factory near the quarry,
\nlarge blocks of limestone are cut into slabs and then polished.
\nThese yellowish, grayish, and sometimes pinkish limestone slabs
\nhave been widely used in Indonesia. For instance, you can see
\nthem covering the walls and floors of the entrance hall at the
\nPresident Hotel, where I am currently staying. These limestones
\nhave been even exported to a number of foreign countries. They
\nare full of fossil corals, hydrozoas, foraminifera and calcareous
\nalgae.<\/p>\n
Perhaps in the future, teachers should bring their students to
\none of the hotels besides the National Museum and ask them to
\ntake a close look at the surface of the limestone walls there.
\nStudents may be curious and will be surprised to find the remains
\nof some creatures that once lived on the floor of the ancient
\nJavanese Sea.<\/p>\n
MAKOTO KATO<\/p>\n
Jakarta<\/p>", "url": "https:\/\/jawawa.id\/newsitem\/limestones-1447899208", "image": "" }, "sponsor": "Okusi Associates", "sponsor_url": "https:\/\/okusiassociates.com" }