Thursday, 27 August 2009

Calcified Grapes and Oranges

Throwing fruit into the waters of Carlsbad, 200 years ago...

Yesterday, my colleague found a rather interesting mineral in our stores. It was next to a St. Aubyn mineral, and looked like a bunch of grapes. After some research, I realised that it was indeed a bunch of grapes! If you look closely at the picture you can see the grape stalk. I needed to check the catalogues to make sure it wasn't a St. Aubyn mineral, as he tends to have strange things like this in his collection. Unfortunately, these grapes are not part of the St. Aubyn collection, however, I managed to discover the truth behind another very peculiar specimen (below).

I have found out that this object is a branch of two oranges, with their leaves, covered in a calcium crust. This mineral would have been made by placing the oranges in the waters of Carlsbad in the Czech Republic over 200 years ago. Count de Bournon wrote about this item in his c1799 catalogue:

"Incrustation de Spath calcaire, faite sur un bouquet de feuilles d'oranger aux quelles étoient adhérentes deux oranges, placé dans les eaux incrustantes de Carlsbad en Bohême une cassure faite, sur le milieu de la réunion des tiges, laisse appercevoir que cette incrustation Spathique, qui est d'un rouge brun foncé à texterieure, est d'un jaune ocreux dans l'intérieur".

Which translated reads:

"Incrustation of calcareous spar, made on a bunch of orange-tree leaves to which two oranges were attached, placed in the encrusting waters of Carlsbad in Bohemia. A break, made on the middle of the junction of the twigs, allows one to see that this sparry incrustation, which is a dark brown red on the outside is yellow ochre inside."

Apparently, it was a common for people to put things in petrifying springs like this to see how long they took to become 'petrified '. It would take approximately two years for such objects, which were then available for sale to visitors there...
All images are © Plymouth City Museum and Art Gallery


  1. Oooo I like these grapes, what a nice interesting find.

  2. Hi Jess

    We visited a "Petrified Well" in Matlock Bath, Derbys. a couple of weeks ago. It was basically a load of old junk being calcated (is that the wrong word) in a little pit. There were old watering cans, bottles, shovels, all turning into stone from a steady drip (drip, drip, drip). Amazing. It was at a crazy aquarium, although I'm not sure it would work with fish. Anyhow they don't mind getting wet.