The origin for argentinian lithophysae with fine colourfull agates in the center is near the town of Mirador in Patagonia. These thundereggs are reaching sizes up to 160 mm in diameter. The mostly intensively dark coloured agates are surrounded by creamcoloured to lightly greenish Perlite. It is difficult to make pictures of these thundereggs which are showing the natural impression of these specimen because of this strong contrast.

The Perlite is is clearly structured: Usually a flower-similar spherulithical formation enriches the interesting pattern of the Thundereggs. Often the Thundereggs are containing only small  agate parts, due to the beautiful contrast with the Perlite Mirador thundereggs arises nevertheless interesting collectors items. The colours of the agates are reaching from different brown and red tones up to blue and yellow. “Water-level-agate” structure is relatively common. An often arising portion from mossy-like agate seems just as characteristic to be too.