Methodology

Begin with the object

Original images remain unchanged. Gum, watermark, backstamps, repairs and routes that cannot be observed are not reported as confirmed.

Let sources support claims

We prioritise issuing authorities, archives, museums, specialist catalogues and scholarship, and state what each source supports.

Valuation is dated evidence

Asking prices are not realised sales; catalogue values are not market estimates. Every valuation belongs to a specific object and date.