RARE 9″ Metasigaloceras rusticum Fossil Chalk Ammonite | Turonian Cretaceous | Dover Kent UK | Alice Purnell Collection

Description

This listing showcases a RARE 9-inch fossil ammonite, Metasigaloceras rusticum, from the Turonian Stage of the Cretaceous Period, discovered in the classic Upper Chalk exposures of Dover, Kent, United Kingdom. A striking and academically important piece, this specimen comes from the distinguished Alice Purnell Collection.

Geological Details:

• Locality: Dover, Kent, United Kingdom
• Geological Period: Cretaceous
• Geological Stage: Turonian (~93.9 to 89.8 million years ago)
• Depositional Environment: Open chalk sea with low-energy conditions; dominated by fine calcareous sedimentation from planktonic organisms
• Formation: Upper Chalk Formation, White Chalk Subgroup (Turonian beds of southeast England)

Paleontological Context: Metasigaloceras rusticum is a lesser-known but distinctive member of the Acanthoceratidae Family, recognised by its broad, ribbed shell and its presence in Turonian ammonite zones. Specimens from the UK are rare and are useful for biostratigraphic zonation of chalk successions.

• Order: Ammonitida
• Superfamily: Acanthoceratoidea
• Family: Acanthoceratidae
• Genus: Metasigaloceras
• Species: rusticum
• Biozone: Turonian — likely within the Mammites nodosoides or Lewesiceras peramplum Zones
• Formally Described by: Pervinquière, early 20th century (possible revisions by Kennedy and Wright)

Morphological Features:

• Broad, planispiral shell structure, ~9 inches diameter
• Strong, rounded ribbing extending across the flanks
• Involute coiling with a slightly flattened venter
• Characteristic pale chalk preservation with light calcitic infilling

Notable Characteristics:

• Rare UK example of a continental European genus
• Found in the iconic chalk cliffs near Dover
• From the highly regarded Alice Purnell Collection, with scientific provenance

Authenticity & Presentation:

• 100% genuine fossil, not a cast or reconstruction
• Supplied with an official Certificate of Authenticity
• The photo shows the actual specimen you will receive
• Scale cube = 1cm — refer to photo for accurate size reference

Additional Notes: This is a seldom-seen British chalk ammonite, rarely offered for public sale. Metasigaloceras rusticum is ideal for collectors of Upper Cretaceous fossils, educational display, or museum-quality curation. A robust and elegant ammonite with great scientific and visual appeal.

All of our Fossils are 100% Genuine Specimens & come with a Certificate of Authenticity.