Natural freshwater pearls
Bildnummer 11741974
| Natural pearls from freshwater mussels. Pearls are accretions of nacre (calcium carbonate) secreted by certain oysters and mussels. The presence of a foreign body (such as a parasite or a grain of sand) within the shell triggers the secretion of nacre by the mollusc's mantle. Thin layers are deposited on the irritant particle and,over several years,a pearl is formed. Although commercially valuable pearls are obtained from freshwater mussels and oysters,the precious pearl comes from species of Margaritifera oysters found in tropical oceans. Cultured pearls are cultivated by inserting fragments of clam shell into the shells of farmed mussels and oysters | |
| Lizenzart: | Lizenzpflichtig |
| Credit: | Science Photo Library / Fleming, Vaughan |
| Bildgröße: | 3763 px × 2480 px |
| Modell-Rechte: | nicht erforderlich |
| Eigentums-Rechte: | nicht erforderlich |
| Restrictions: | - |
Preise für dieses Bild ab 15 €
Universitäten & Organisationen
(Informationsmaterial Digital, Informationsmaterial Print, Lehrmaterial Digital etc.)
ab 15 €
Redaktionell
(Bücher, Bücher: Sach- und Fachliteratur, Digitale Medien (redaktionell) etc.)
ab 30 €
Werbung
(Anzeigen, Aussenwerbung, Digitale Medien, Fernsehwerbung, Karten, Werbemittel, Zeitschriften etc.)
ab 55 €
Handelsprodukte
(bedruckte Textilie, Kalender, Postkarte, Grußkarte, Verpackung etc.)
ab 75 €
Pauschalpreise
Rechtepakete für die unbeschränkte Bildnutzung in Print oder Online
ab 495 €