| Geological age | Most dinosaur fossils come from the Mesozoic Era, approximately 252 to 66 million years ago. Non-avian dinosaurs lived from roughly 235 to 66 million years ago. | Extreme age, rarity, and the limited number of well-preserved specimens increase scientific, educational, and collector interest. | Request a documented geological context and avoid specimens with a missing or suspicious excavation history. |
| Scientific importance | A fossil can preserve information about anatomy, evolution, behavior, paleoecology, and the geological environment in which it was found. | Specimens with clear scientific value may be more important to research and public education than to private ownership. | Consider whether qualified researchers and public institutions have had appropriate access to study the specimen. |
| Completeness and preservation | Rarity, anatomical completeness, preparation quality, authenticity, and the amount of original fossil material are commonly used valuation factors. | More complete and better-preserved specimens generally attract greater interest, while repairs, reconstruction, or composite elements can materially affect value. | Require an independent condition report that identifies restoration, replacement material, reconstruction, and replicas. |
| Provenance | Provenance is the documented ownership, excavation, publication, exhibition, and movement history of a specimen. | A continuous provenance record reduces the risk that the fossil was excavated or exported unlawfully. | Obtain excavation records, prior ownership documents, permits, invoices, publication references, and transport records where available. |
| National ownership laws | Many countries treat fossils found on public land or in protected areas as state property, cultural heritage, or protected geological material. Rules vary by jurisdiction. | A fossil may be legally excavated in one country but illegal to export, sell, or import under another country’s law. | Verify the law of the country of origin, the export country, the transit countries, and the destination country before purchase or shipment. |
| UNESCO 1970 Convention | The 1970 UNESCO Convention addresses the illicit import, export, and transfer of ownership of cultural property. Its application to fossils depends on national implementation and classification. | Fossils classified as protected cultural or natural heritage may be subject to return claims, import restrictions, or customs scrutiny. | Check whether the origin and destination countries are parties to the Convention and whether relevant domestic implementing rules apply. |
| UNIDROIT 1995 Convention | The 1995 UNIDROIT Convention provides rules concerning stolen or illegally exported cultural objects, including possible restitution or return procedures where applicable. | Later discovery of unlawful removal can create ownership disputes, restitution obligations, and significant financial loss. | Use enhanced due diligence for high-value specimens and retain evidence showing reasonable investigation of title and export legality. |
| CITES relevance | CITES primarily regulates international trade in living species and listed specimens. Fossils are generally outside its scope because they are not living biological specimens, but national rules may impose additional controls. | Buyers should not assume that the absence of a CITES requirement means that a fossil is legal to export or import. | Confirm the requirements of customs, heritage, mining, protected-area, and wildlife authorities in every relevant jurisdiction. |
| Excavation ethics | Responsible excavation records the exact locality, stratigraphic layer, associated material, and collection circumstances. Removing a fossil without recording its context can destroy scientific information. | Loss of geological context can reduce research value even when the fossil itself is visually attractive. | Prefer specimens excavated with documented scientific methods and reject material linked to protected sites, looting, or clandestine digging. |
| Authenticity and restoration | Commercial specimens may contain repairs, casts, painted fills, reconstructed sections, or composite parts from more than one individual. | Misrepresentation can inflate prices and undermine scientific integrity. | Obtain written disclosure, high-resolution photographs, preparation notes, and an independent specialist examination before purchase. |
| Customs and export documentation | International shipments may require export permits, import permits, cultural-property certificates, declarations of origin, invoices, and accurate commodity descriptions. | Incomplete or inaccurate paperwork can lead to seizure, delays, penalties, or refusal of entry. | Use accurate descriptions and declared values, preserve all permits, and ensure the shipping route matches the authorized documentation. |
| Black-market risk | Unprovenanced fossils can originate from unauthorized excavation, protected areas, conflict zones, or trafficking networks. | Low-price offers, urgent sales, anonymous ownership histories, and unusually rare specimens may signal elevated legal and ethical risk. | Apply enhanced due diligence, document the decision-making process, and walk away when provenance cannot be reasonably verified. |
| Public and scientific access | Fossils can provide long-term public benefit through research, conservation, education, and museum display. | A purely private sale may limit access to specimens with exceptional scientific or cultural significance. | Consider lending, donating, publishing, or placing scientifically important specimens with qualified public or research institutions. |
| Risk classification | Lower risk complete provenance, legal export evidence, transparent restoration, and independent authentication. | Clear documentation supports lawful trade and reduces the probability of title disputes or customs intervention. | Maintain a complete compliance file for the entire ownership and transport history. |
| Risk classification | Medium risk partial provenance, uncertain restoration, or unclear rules in the country of origin. | Unresolved gaps may become serious problems when the specimen is resold, exported, or examined by authorities. | Pause the transaction until missing records and legal opinions are obtained. |
| Risk classification | High risk recent excavation, protected-site origin, anonymous seller, implausibly low price, or refusal to provide documents. | These indicators are consistent with possible illicit excavation, trafficking, fraud, or ownership disputes. | Do not purchase, transport, or promote the specimen without credible proof of lawful origin and title. |