Damesites aff. ainuanus Ammonite Fossil Japan Campanian with COA

Description

Genuine Damesites Ammonite Fossil

This genuine ammonite fossil is identified as Damesites aff. ainuanus and comes from Nakagawa-cho, Nakagawa-gun, Hokkaido, Japan. It dates to the Campanian Stage of the Upper Cretaceous and is a carefully selected specimen with valuable genus, comparative species identification, geological age, and detailed locality information. The photographs show the actual fossil offered for sale, so the ammonite pictured is the exact specimen you will receive.

The abbreviation aff. indicates that the fossil shows close affinity with Damesites ainuanus while preserving the cautious comparative identification appropriate for the specimen. Damesites was an extinct marine cephalopod with a coiled, chambered shell. During growth, the animal formed progressively larger chambers around the outer whorl. The living ammonite occupied the final body chamber, while older sealed chambers contributed to buoyancy control.

Campanian Upper Cretaceous Age

The Campanian is a stage of the Late Cretaceous Period, approximately 84 to 72 million years ago. Marine environments during this interval supported diverse ammonites alongside bivalves, gastropods, inoceramids, fish, and marine reptiles. After death, an ammonite shell could settle on the sea floor and become buried within sediment. Compaction, mineral replacement, and geological change then preserved portions of the shell as a fossil.

Ammonites evolved rapidly and were widely distributed through Cretaceous oceans. Their changing shell forms make them valuable index fossils, helping geologists compare sedimentary sequences and establish relative ages. The documented Campanian age gives this specimen a clear position within the Upper Cretaceous succession before ammonites disappeared at the end of the period.

Nakagawa, Hokkaido Provenance

Hokkaido is internationally known for richly fossiliferous Cretaceous marine rocks and beautifully preserved ammonites. The Nakagawa area contains sedimentary deposits that record ancient environments along the northwestern Pacific margin. Fossils from this region provide evidence of a diverse marine ecosystem and are appreciated for both their scientific context and distinctive preservation.

The detailed Nakagawa-cho and Nakagawa-gun locality gives this fossil more collecting and educational context than an entirely unlocalised specimen. It can complement a collection arranged by Japanese region, Cretaceous stage, ammonite genus, or ancient marine environment.

Shell Form and Collectable Detail

Damesites ammonites are generally recognised for compressed, relatively involute shells with fine ornament and an efficient streamlined profile. Examine the photographs for visible whorls, shell outline, umbilical region, surface texture, matrix, and preserved details on this individual example. Whorl proportions, degree of compression, ornament, keel development, and sutural features are among the characteristics used when comparing ammonites and interpreting growth.

Natural colour, mineral texture, small breaks, areas of wear, and differences in surface preservation reflect the fossil’s long geological history. Every fossil preserves a different balance of original shell, mineral replacement, and surrounding rock. The multiple photographs show this exact specimen from useful angles and present its condition, proportions, texture, and natural display character more accurately than a generic image could.

Exact Specimen and Full Sizing

Full sizing is shown in the photographs, which provide the best scale information for this individual fossil. The images are not stock photographs and do not represent a similar piece. They show the exact Damesites aff. ainuanus ammonite fossil that will be supplied.

Authenticity and Presentation

This is a genuine fossil specimen and includes a generic Certificate of Authenticity card with a lifetime guarantee. It has been carefully chosen for its characteristic ammonite form, Campanian age, detailed Nakagawa locality, Japanese provenance, and natural geological character. It makes a distinctive addition to a cabinet collection, educational display, office, study, or gift for anyone interested in authentic Upper Cretaceous fossils, Japanese palaeontology, or ammonite evolution.