A magnet was not used to get the broken drill bit out. In fact they had to manufacture on site what's called a "spider drill" which had an open spiral toothed design at the end of the drill to try to surround the broken bit. Using the pressure of down force, the teeth would collapse around the bit to capture it.
Mamani recalls that the land the mine is located was Bolivian and was taken by Chile in 1881. He references the War of the Pacific (1879-1884), between Chile and an alliance between Peru and Bolivia. However, in common discussions about this subject, Chileans and Bolivians would reference the year 1879, when it began, instead of 1881.
The movie depicts the men sleeping on the ground and just waiting around for the rescue hole to be drilled after they were found. In reality they were sent cots down to sleep on. Also they were all working in 8 hour shifts throughout the day to clear the debris made from the drilling of the hole.
In the opening scene, Alex Vega wears Universidad de Chile's commemorative Copa Sudamericana shirt. This soccer team won its first (and only) Cup in 2012, 2 years after the events take place (2010).
On a few instances throughout the film Toyota Hilux pickup trucks of the 2011 face lift can be seen.
Some of the letters at the beginning of the Chilean License Plates (such as G) were not yet available as of 2010.