The keris, a dagger from Southeast Asia, was named a Masterpiece of Humanity's Oral and Intangible Heritage by UNESCO in 2005. The keris is a dagger with an unusual blade shape made possible by switching between iron and pamor (nickelous iron laminations). A number of the most well-known representations of the keris may be seen on the bas-reliefs of the Borobudur and Prambanan temples. Through maritime trade links and the growing influence of the Majapahit Empire in Java around the year 1492, keris culture spread throughout the Indonesian archipelago as far as Malaysia, Singapore, Thailand and the Philippines.  

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