Molten rockfall on Mount Sinabung volcano. Footage of glowing lava and rocks cascading down the side of Mount Sinabung (2460 metres), an andesitic stratovolcano in Sumatra, Indonesia. These rocks broke off from a failure point in the volcano's lava dome. Due to the low gas content, the result was a rockfall rather than the a pyroclastic flow. Inactive for over a thousand years, this volcano briefly awakened in 2010, after which a larger eruption occurred from 2014 onwards. Footage obtained in July 2015.