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The Encyclopedia of Horology

Tool · Planispheric astrolabe

Iranian astrolabe in the style of 'Abd al-A'imma

Partially verified

According to Sotheby's, this unsigned Iranian astrolabe is executed in the style of late 17th-century Isfahan instrument-maker 'Abd al-A'imma. The front of the throne is engraved with a cartouche containing the Qur'anic Throne Verse. The instrument includes five plates serving latitudes 27°, 30°, 31°, 32°, 33°, 34°, 36°, 38°, and 40°, as well as a plate of horizons. The back is fitted with an alidade, shadow scales, a solar quadrant, and a trigonometric quadrant, alongside prominent circular turning markings noted by the cataloguer.

Front and back views of the Iranian planispheric astrolabe with rete, alidade, and suspension cord
Front and back views of the Iranian planispheric astrolabe with rete, alidade, and suspension cord — Sotheby's. Rights pending — permission not yet requested. Original source

Catalogue identity

Source
www.sothebys.com
Category
Tool · Planispheric astrolabe
Maker / attribution
'Abd al-A'imma (attributed style)
Reference
Not recorded
Catalogue / lot identifier
190
Source-reported date
late 17th century style
Country
Iran

Source-reported attribution and specifications are not independent authentication. A listing does not establish present ownership, current display, availability or permission to reproduce.

Object description

Identity and Attribution

This unsigned Iranian planispheric astrolabe is attributed to the late 17th-century Isfahan tradition associated with the instrument-maker 'Abd al-A'imma. The attribution is based on the quality and style of the execution and engraving.

The cataloguer notes that the instrument is not a deliberate fake bearing the maker's name, but does not provide further provenance.

Evidence for this section
  • “whilst this little astrolabe is unsigned, the quality and style of its execution and engraving suggest that it might have been made by 'Abd al-A'imma”
  • “This is certainly not one of the deliberate fakes that bear his name”

Components and Configuration

The instrument includes five plates serving the following latitudes: 27°, 30°, 31°, 32°, 33°, 34°, 36°, 38°, and 40°, in addition to a plate of horizons. The front of the throne is engraved with a cartouche featuring the Qur'anic Throne Verse.

The horse and pin are replacements. The exterior and one plate show signs of abrasion, pitting, and patination.

Evidence for this section
  • “The latitudes served by the plates are 27°, 30°, 31°, 32°, 33°, 34°, 36° and 38° and 40°, and there is also a plate of horizons.”
  • “the celebrated "Throne Verse" from the Qur'ân is engraved in a cartouche on the front of the throne”
  • “horse and pin replaced”
  • “areas of abrasion, pitting and patination particularly to exterior and one of the plates”

Reverse and Mechanical Observations

The reverse of the astrolabe is equipped with a trigonometric quadrant, a solar quadrant, and shadow scales.

The back of the instrument and the back of the throne display circular markings from severe turning, which reveal a black underlying metal. No explanation for these marks is provided by the source.

Evidence for this section
  • “The back bears the standard trigonometric quadrant, a solar quadrant and shadow scales.”
  • “the back of this instrument has been severely turned and there are circular markings on the back as well as on the back of the throne. The metal underneath appears to be black.”

Open research questions

  • What is the composition of the black underlying metal revealed by the turning on the reverse?
  • What is the physical cause of the circular markings on the back of the instrument and throne?

Source evidence

Recorded claims and source quotations for Iranian astrolabe in the style of 'Abd al-A'imma
FieldSource-reported valueSource quotation
Maker attributionIn the style of 'Abd al-A'imma“in the style of the celebrated instrument-maker of late-17th-century Isfahan, 'Abd al-A'imma”
Plate count5 plates“5 plates”
Throne inscriptionThrone Verse from the Qur'an“the celebrated "Throne Verse" from the Qur'ân is engraved in a cartouche on the front of the throne”
Plate latitudes27°, 30°, 31°, 32°, 33°, 34°, 36°, 38°, and 40°“The latitudes served by the plates are 27°, 30°, 31°, 32°, 33°, 34°, 36° and 38° and 40°”
Reverse markingsTrigonometric quadrant, solar quadrant, and shadow scales“The back bears the standard trigonometric quadrant, a solar quadrant and shadow scales.”
BibliographyMayer, Islamic Astrolabists“Bibliography: Mayer, Islamic Astrolabists , s . v .”

Visible details

  • Front shows a pierced rete with vine-like tracery over engraved latitude markings.
  • Reverse features a diagonally mounted alidade and concentric turning marks.
  • Top loop is attached with a suspension ring threaded with red woven cord.

Research qualifications

  • Instrument is unsigned; attribution to 'Abd al-A'imma is based solely on stylistic analysis.
  • Cataloguer notes the horse and pin are replacements.
  • The back shows severe turning and unexplained circular markings over dark underlying metal.

Photograph identity and source facts were screened before import; rights clearance remains pending.

Consulted source

(#190) A second elegant Iranian astrolabe in the style of the celebrated instrument-maker of late-17th-century Isfahan, 'Abd al-A'imma

Reviewed 2026-10-25 · Record 334f8cc754

Terms in this record

Glossary explanations for terms named in this object’s record.

Other planispheric astrolabe records