Philippinites, or rizalites are

tektite Tektites (from grc, τηκτός , meaning 'molten') are gravel-sized bodies composed of black, green, brown or grey natural glass formed from terrestrial debris ejected during meteorite impacts. The term was coined by Austrian geologist Franz ...

s found in the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. They are considered to be about 710,000 years old on the average and generally ranging in size from millimeters to centimeters. Their age corresponds with the age of other tektites in the Australian strewn tektite field. In 1964, a very large philippinite, weighing with dimensions 6.5 x 6.2 x 5.2 cm, was purchased by the

University of California, Los Angeles The University of California, Los Angeles (UCLA) is a public land-grant research university in Los Angeles, California. UCLA's academic roots were established in 1881 as a teachers college then known as the southern branch of the Californ ...

Department of Astronomy. The heaviest philippinite ever found weighs in its splash-form, which is also the heaviest tektite of this kind.

Etymology

The term rizalite was named after the

Philippine province In the Philippines, provinces ( fil, lalawigan) are one of its primary political and administrative divisions. There are 82 provinces at present, which are further subdivided into component cities and municipalities. The local government uni ...

Rizal Rizal, officially the Province of Rizal ( fil, Lalawigan ng Rizal), is a province in the Philippines located in the Calabarzon region in Luzon. Its capital is the city of Antipolo. It is about east of Manila. The province is named after Jos� ...

where the first black tektites were rediscovered in October 1926 at

Novaliches Novaliches is a place that forms the northern areas of Quezon City, and encompasses the whole area of North Caloocan. Etymology The name Novaliches came from the name of the small village of Novaliches in the town of Jérica, Spain. It was ...

(which was then part of Rizal). Although, it was only in 1928 that the term was proposed by American anthropologist

H. Otley Beyer Henry Otley Beyer (July 13, 1883 – December 31, 1966) was an American anthropologist, who spent most of his adult life in the Philippines teaching Philippine indigenous culture. A.V.H. Hartendorp called Beyer the "Dean of Philippine ethnolo ...

, dubbed as the father of Philippine tektite studies, to refer to tektites found in the Philippines. Philippinite has become the more favored term because other tektites were found in other areas of the Philippines such as the

Bicol region Bicol, known formally as the Bicol Region or colloquially as Bicolandia ( bcl, Rehiyon kan Bikol; Rinconada Bikol: ''Rehiyon ka Bikol''; Waray Sorsogon, Masbateño: ''Rehiyon san Bikol''; tl, Rehiyon ng Bikol), is an administrative region of ...

and the town of Anda in the province of

Pangasinan Pangasinan, officially the Province of Pangasinan ( pag, Luyag/Probinsia na Pangasinan, ; ilo, Probinsia ti Pangasinan; tl, Lalawigan ng Pangasinan), is a coastal province in the Philippines located in the Ilocos Region of Luzon. Its cap ...

. Some early authors referred to Philippine tektites as "obsidianites" but that too has fallen out of use due to the introduction of the term philippinite by succeeding authors.

Uses

In ancient Philippines, tektites were used by early settlers in the Philippines as arrowheads and other tools as well as decorative purposes. During the Philippine Iron Age, due to the polish features of philippinites found in graves, it was evidenced that philippinites were used as amulets or charms. In modern times, it is generally used as a collector's item.

Composition

The following table details the chemical composition of philippinite:

Notes

:# Splash-form tektites are tektites that are shaped like spheres, ellipsoids, teardrops, dumbbells, and other forms. They have shaped this way due to the ejecta or splash of silicate liquid following a

meteorite impact An impact event is a collision between astronomical objects causing measurable effects. Impact events have physical consequences and have been found to regularly occur in planetary systems, though the most frequent involve asteroids, comets or m ...

, scattering them to a distance up to thousands of kilometers.

References

{{Impact cratering on Earth Glass in nature Impact event minerals Amorphous solids Geology of the Philippines