أرسل هذا في رسالة قصيرة: The origins of transparent and non-transparent white pumice: A case study of the 52 ka Maninjau caldera-forming eruption, Indonesia

  ______     ___      _____     ______    _  _   
 /_   _//   / _ \\   / ____||  /_   _//  | \| || 
 `-| |,-   | / \ || / //---`'   -| ||-   |  ' || 
   | ||    | \_/ || \ \\___     _| ||_   | .  || 
   |_||     \___//   \_____||  /_____//  |_|\_|| 
   `-`'     `---`     `----`   `-----`   `-` -`