Identification
ID in this catalogue SC GRM 15735
Type Unclassified. BSDP (Graßhoff 2015) lists it as "conical", but it clearly is not in the standard sense.
Current Location Graeco-Roman Museum, Alexandria, Egypt  
Catalogue Numbers

15735

Dialface ID: 448 

Provenance Ibrahimiya, outside Alexandria. Excavated in the early 1900s. (Locher (1993)
Date 1st century CE-2nd century CE 
Dimensions Unknown 
Material Plaster. This being the only sundial in the BSDP database listed as being in plaster, and the confusion around a replica in the same museum in Alexandria of a British Museum sundial, leads the present researchers to wonder it this could be a cast of a different sundial.
Markings and inscriptions Eleven hour lines seem to have been preserved.
Notes

Not in the catalogue by Gibbs (1976)

Has a shadow-receiving surface of negative, roughly hyperboloidal curvature (Locher (1993). This makes it unique in shape and not, strictly, a member of any of the Gibbs categories. Only the angle between the flat top and the inlcined front surface matching Alexandria's latitude seems to convince Locher that this is intended to be a sundial (a decorative architectural feature would be another possibility).

The combination of the GRM being currently closed, only one low resolution image being available, the shape, and the material make this an interesting and mysterious object.

Literature

Locher (1993)

Graßhoff (2015)

Images

The BSDP database (Graßhoff 2015) does not have a photograph but the black-and-white image in Locher (1993) is available online here.