This is a sizeable chunk of matrix boulder opal from the Quilpie mines in Queensland, Australia. The chunk is made of ironstone, which contains veins of precious opal in blue and turquoise. It is not of gemstone quality, but is meant for display purposes for collectors. The stone has a roughly triangular base, which measures 4cm x 4cm x 3.5cm and it is ca. 2,5cm high. One side of the chunk is curved and this side has been smoothed off and polished. The rest of the stone has been left in its natural state. It registers as overload on my jeweller’s scales but weighs about 75 grams on rough kitchen scales. This stone would make a fine exhibit in anyone’s display cabinet.