Scientific Analysis

As technology becomes ever more complex so too does scientific examination of an artwork. X-radiography and IRR (infrared reflectography), MA-XRF (macro X-ray fluorescence), digital photomicrography, and dendrochronology (dating by tree rings). Fine Art Investigations arranges scientific analysis with qualified conservators, with the owner’s permission, when needed.

FAI staff concentrates on research but is fascinated by the breadth of knowledge and the technical skill involved in scientific examination. A specific example is an antebellum portrait miniature whose provenance connected the piece to the family of Abraham Lincoln’s wife, Mary Todd. Before contacting FAI, the owners had already consulted portrait miniature experts who performed the initial step in scientific analysis:

Examination in Normal Light

Three portrait miniature experts confirmed that the ivory, the frame, and the painting itself were genuinely antebellum with a date of execution between 1830 to 1850. They could tell the owners nothing more about the small painting that is now referred to as the Mathisen Miniature.

The owners contacted Fine Art Investigations who determined, through clothing and hair style, that the time frame could be narrowed down to 1840-1842. Light clothing fabric indicated that the season was summer. For the region, FAI initially chose the Ohio River Valley because many artists of the era, whether traveling east and west or north and south, passed through on the network of rivers. The selection included Kentucky, the home state of the Todd family. By comparing the miniature with the work of 42 artists, through connoisseurship, and Morellian analysis, FAI discovered Joseph Henry Bush to be the probable artist. Further research revealed that in August-September 1841, Abraham Lincoln, who was then a 32-year-old, debt-free circuit attorney, visited his friend Joshua Fry Speed at the Speed estate in Louisville. Bush was the portrait artist for the Speed family. The time was eight months after Abraham Lincoln broke his engagement to Mary Todd.


Joseph Henry Bush
Aqueous Medium on Ivory 1 7-8 x 2 3-16 inches

Art Analysis & Research (AA&R) (now Art Discovery) in New York City performed a thorough scientific examination on the miniature. Staff analyzes materials and methods used to create paintings, determines condition and age, and helps confirm attributions or detect fakes.”  Details of the examinations are prohibited from being published publicly, but with ultraviolet (UV) light and infrared (IR) light, with digital photomicrography, and with paint sampling. AA&R confirmed the age and authenticity of piece.

Infrared (IR) Light

I can share an example of scientific examination with Infrared Radiology with a re-discovered portrait of artist George Caleb Bingham’s cousin’s husband, John A. Trigg. Conservators at the de Young Museum-Fine Arts Museums of San Francisco performed the scientific examination. The under-drawing reveals how much Bingham struggled to paint ears and how he altered the shape of the collar. In infrared light, bad in-filling from a restoration was even more visible in IR light than in normal light.


George Caleb Bingham
John A. Trigg, ca. 1844
Natural Light


George Caleb Bingham
John A. Trigg, 1844
Infrared Radiology