Bring your auction to collectors worldwide!
Get listed nowBy subscribing, you are agreeing to the privacy policy. Unsubscribe anytime.
Barnebys HQ
Brahegatan 10
BOX 5038
114 37 Stockholm
All auctions / Ethnographical / Fossilized Sectioned Ammonite (Cleoniceras) with...
Fine preservation of the internal chambered structure and rich mineral crystallizations — This exceptional specimen consists of a fossil ammonite of the genus Cleoniceras, sectioned and polished to reveal its magnificent internal structure. The genus identification of Cleoniceras is supported by the typical complex sutures and the morphology of the shell, indicative of a cephalopod organism that lived during the Cretaceous period. The cross-section highlights the chambers (gas chambers) separated by septa, a fundamental diagnostic element for the classification of these marine invertebrates. The visual analysis reveals an extraordinary fossilization with a rich variety of colors and textures. The internal chambers have been filled by secondary crystallizations of aragonite and calcite, ranging from honeyed and amber tones to translucent whites and pearly greys. The suture lines, once filled with sediment, are now outlined by a chromatic contrast that enhances their intricate pattern. Small geodes dotted with shiny microcrystals of calcite can also be observed inside some chambers, testifying to a highly complex and prolonged secondary mineralization process. The origin of this specimen is Madagascar, a geologically renowned area for producing ammonites of exceptional quality and preservation. The formation context dates back to the Cretaceous period, an era approximately between 145 and 66 million years ago. During this period, Madagascar was part of an active marine environment favorable to the life of ammonites and their subsequent fossilization, often with permineralization processes that preserve internal details. The aesthetic quality of this lot is remarkable, especially for the perfect symmetry of the section and the luster of the polished surface that maximizes color contrast and depth. The visibility of the internal chambers, with fine details, and the presence of multiple generations of aragonitic and calcitic crystallization make it a museum piece. The warm tones of brown and orange combined with white and grey create a harmonious and sophisticated visual impact. The state of preservation is excellent, with no signs of significant damage or invasive restorations. The two halves fit perfectly, testimony to a segmentation and polishing work carried out with precision. The surfaces are smooth and reflective, allowing a clear observation of the internal structures. The lot also includes the appropriate supports for display, enabling an elegant and stable presentation of the ammonite. From a collecting standpoint, a Cleoniceras ammonite that is sectioned and crystallized of this size and quality is highly sought after. Specimens showing such structural integrity and rich internal mineralization are considered top pieces for any fossil or mineral collection. This lot offers not only an opportunity for paleontological study but also a piece of great aesthetic beauty, uniting geological history with the refined art of nature. Its Malagasy origin, combined with the magnificence of its fossilization, makes it a piece of notable educational and display value."} }46) 4 null'
Estimate:£466.53
To the auctionView all items fromCatawikiorEthnographical
Estimate:
£466.53
OCT 17 | 10:00 PM
Bring your auction to collectors worldwide!
Get listed now£7.6
Two gilded bronze Singha temple lions, Thailand, first half of the 20th century
10/07/2026
£186.47
Est: £170.79
