The National Center for Preservation Technology and Training (NCPTT) and The Museum of Fine Arts Houston are partnering to host a three-day hands-on workshop on Fiber Identification and Analysis for conservation. The workshop will be held March 24-26, 2015 at the MFA Houston in Houston, TX. The workshop’s main instructor is Nicholas Petraco with secondary instruction by Fran Gale. This workshop is only open to 20 participants, so please register early to reserve your spot. Tuition for the class is $399.
This course covers basic polarized light microscopy (PLM) and methods of sampling, characterization and identification mammalian hair and selected natural and synthetic fibers. Emphasis will be placed on hands-on exercises involving sample preparation and specimen manipulation as well as the characterization and identification of real life specimens.
March 24th, Day 1 8:30-5:00
- Basic polarized light microscopy
- Geometric optics
- Reflection and refraction
- Refractive index and contrast
- Beck line
- Isotropy and anisotropy
- Birefringence and retardation
- Interference Chart
- Characterization of hair, natural and synthetic fibers
March 25th, Day 2 9:00-5:00
- Introduction to mammalian taxonomy
- Cortex, medullar and cuticle
- Macroscopic and microscopic hair anatomy
- Macroscopic hair features: color, length, thickness, shape and banding
- Basic sample preparation and mounting media
- Cross-section preparation
- Methods for observing cortex and medullar
- Medullary Index
- Methods for observing cuticle scale patterns
- Root morphology
- Damage and deterioration
- Study of scale patterns and their variation along the hair shaft
- Reference collections
March 26th, Day 3 9:00-3:00
- Review previous day’s work
- Identification of hairs from selected groups: domestic animals, pets, commercial furs.
- Distinguishing between human and animal hairs
- Distinguishing between cat and dog hairs
- Distinguishing between cow, horse, deer, squirrel and rabbit hairs
- Review of available hair and fiber atlases and reference articles
- Preparation of standard collections
All portions of the workshop will be held at the Museum of Fine Arts, Houston. The MFAH is located at 1001 Bissonnet St, Houston, TX 77005.
Nicholas Petraco Sr., BS Analytical Chemistry, MS Forensic Science, very extensive post-degree university coursework in art, art history and heritage conservation, Fellow of New York Microscopical Society (NYMS), Fellow of American Academy of Forensic Science, Diplomat of the American Board of Criminalistics, Mr. Petraco served in the New York City Police Department 1968 – 1990, as Police Laboratory detective/criminalist, and senior trace evidence forensic microscopist from May 1982 until April 1990. As an independent consultant Mr. Petraco has aided hundreds of investigations since 1993, and since 1999 has been designated Technical Leader in Criminalists for NYPD’s Forensic Investigation division. Mr. Petraco has advised or joined diverse art investigations, has advised or joined thousands of prosecutor and defense attorney death investigations, and he has given civil or criminal court expert testimony in over 500 trials. In forensics literature Mr.
Petraco is the author or co-author of more than 100 journal articles and notes, CD’s, 9 book chapters, and 5 books. Mr. Petraco lectures and instructs very often on the use of light microscopy, especially stereomicroscopy and polarized light microscopies, in identifying paint pigments, binders and finishes, synthetic and natural fibers and hair, and diverse other materials of interest. On March 26, 2007, he was promoted to Assistant Professor and granted a life’s work, background and experience equivalent to PhD waiver by CUNY Committee on Staff and Administration. Professor Petraco is a member of the CUNY graduate center’s PhD committee for forensic science, and he has taught microscopy, micro-chemical and instrumental analysis as well as forensic science to forensic scientists, art conservators and others at John Jay College of Criminal Justice, CUNY, the American Museum of Natural History in NYC for NYMS, at the FBI academy in Virginia, at NYU’s Institute of Fine Arts, and at other centers and institutions.