13 January 2012

Sand Roses


Maybe everyone knows what a Sand Rose is. I didn't so here it is for those ignorant like me.

We're looking at Rose des Sables (Sand Roses) which were being sold as decorative pieces in Menton at Christmas. They come from the desert in North Africa - perhaps Tunisia as they were for sale on a Tunisian stand in the Christmas market.

They are formed in the desert when gypsum crystals including sand mix with water. However, for these roses to take shape, the gypsum needs to be slightly below the desert surface and just above ground water. The colour varies from beige to orange pink.

The same phenomenon can also occur as a result of rain, which dissolves the gypsum which then rises to the surface and crystallizes as the water evaporates.

These roses, whose dimensions range from a few centimeters to more than one meter are rarely found on the desert floor but are more often buried under several meters of sand. Once collected, take care of them because, as a result of rain, gypsum dissolves again, the crystals break up and, like all flowers, your desert rose may fade.

There is a legend - I love this story - that the roses are the result of petrification when sand is mixed with camel urine !

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Il est possible que vous sachiez ce qu'est une Rose des Sables. Si ce n'est pas le cas, voila l'explication pour les ignorants comme moi.

Voici des Roses des Sables qui ont été vendues comme pièces décoratives à Noël à Menton. Elles viennent du désert d' Afrique du Nord - probablement de Tunisie puisqu'elles étaient vendues sur un stand tunisien du marché de Noël.

Elles se forment dans le désert quand des cristaux de gypse inclus dans du sable se mélangent à de l'eau et que celle-ci s'évapore. Cependant, pour ces roses prennent forme, le gypse doit se trouver dans la partie supérieure d'une nappe phréatique et légèrement en dessous de la surface du désert. Leur couleur varie du beige au rose orangé.

Le même phénomène peut aussi se produire à la suite de pluie, qui dissout le gypse lequel s'élève alors à la surface et se cristallise quand l'eau s'évapore.

Ces roses, dont les dimensions varient de quelques centimètres à plus d'un mètre sont rarement trouvées sur le sol du désert, mais sont le plus souvent enfouies sous plusieurs mètres de sable. Une fois collectées, il faut prendre soin d'elles car en cas de pluie, le gypse se dissout à nouveau et les cristaux se brisent, alors comme toutes les fleurs, votre rose du désert peut se faner.

Il existe une légende - j'aime cette histoire - selon laquelle les roses sont le résultat de la pétrification du sable mélangé avec de l'urine de chameau!

10 comments:

  1. Born from wind and rain! I have a few of them, I like them, they are special, not really stone, not really sand, just special..

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  2. I picked up lots of these in the Sahara years ago, and still have some, including a huge one that I handle with kid gloves...figuratively.

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  3. haha, i thought you were going to say "mixed with tear"s...when i got to "camel urine" there was an audible guffaw in my little attic.

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  4. Really nice! ... and thanks for the explanation(s)! :-)

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  5. i'm a first time visitor - what a fascinating post & blog

    happy to learn something new today

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  6. I've learned something new today! Very interesting.

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  7. Hi Jilly, I never heard about sand roses... Thanks for the explanation!
    Have a nice weekend!
    Barbara from Germany

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  8. This is what I love most about other people's blogs...you always get to learn something new. Thanks for the info'.

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  9. Yes sand roses are special. My mother has a couple, which I have always found fascinating.

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  10. I think these are beautiful... how do you take care of them? do they need sun? shade? food?

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