Thursday, July 19, 2012

HOW TO APPRAISE & AUTHENTICATE ANTIQUITIES

Appraising and authenticating antiquities are two distinct processes which help in the understanding of the objects themselves. In the best case scenario, the appraiser and the authenticator work together to form a complete picture of what the item is, where it came from, the date of creation, the condition, and the value.

Appraising

Appraisers come from a variety of educational backgrounds and possess numerous specialties. Although most appraisers are not experts in every field, they do have an understanding of how to research a variety of items to determine their origin and monetary value. Appraisers invariably spend hours scouring auction results, galleries, and libraries for the information about an object. Furthermore, they often depend on connections in academia, archaeology, galleries and auction houses to help them come to a conclusion about the items they are appraising. An appraiser’s ultimate goal is to put a value on the work which properly reflects the market. In the United States, there are three major appraisal organizations: Appraisers Association of America, American Society of Appraisers, and International Society of Appraisers. Each of these organizations has a searchable database of well trained professionals who were admitted by passing qualifying exams or other processes. Below are the most common elements of a properly prepared antiquities appraisal.

Elements of a Properly Prepared Antiquities Appraisal

• Item
A brief description of the type of item being appraised. For example, “Ptolemaic Ceramic Oil Lamp.”
• Size
An accurate measurement of the length, width, and height of the item.
• Medium
The materials used to create the antiquity.
• Signature or Markings
Any mark that might give additional information which is located directly on the antiquity.
• Date of Creation
If the exact date is unknown, dating the item to a period or a range of years. For example, “Circa 150 BCE to 50 CE.”
• Condition
Inspect the piece for rust, cracks, deterioration, and wear.
• Provenance
Research and list any known owners of the work, when and where it was acquired, and the original location and date of discovery.

Authenticating

Authentication of antiquities can be complicated since it takes a comprehensive understanding of scientific methods, the latest academic research, and a personal knowledge of the expected attributes. Like appraisers, authenticators come from a variety of backgrounds. They may specialize in scientific analysis, documentation, and connoisseurship. An authentication company may have a variety of experts on staff each of whom may weigh in on an item in their particular area. Below is a detailed explanation of the more common scientific and research methods.

Scientific Authentication

Thermoluminescence (TL)
This method can tell the observer how much time has elapsed since the clay was fired. In this process, the clay is heated to a high temperature. Once it reaches that temperature a faint violet blue light is emitted and then measured using a sensitive detector.
• Radiocarbon Dating
This type of dating is an absolute dating technique. It works by determining the ratio of radiocarbon against stable carbon in the sample. All living organisms are made of carbon. A very small amount of this carbon is C-14 which is unstable and radioactive. When the organism dies it disintegrates at a known rate thus making it easier for scientists to determine the age.
• Computer Tomography (CT Scanning)
Although this process does not scientifically date an antiquity it does give an overall 3-dimensional image. This information can provide information concerning previous repairs, oxidation, deterioration, and the techniques used to actually make the work.

Researched Authentication

• Provenance
Researching the original place of purchase and the history of ownership of an antiquity is important. Knowing that the piece was in the collection of a scholar or major collector helps others understand that the item is what it is purported to be. Further, documented evidence of when and where the antiquity was originally found may help establish the age of the piece.
• Scholarly References and Attributes
This step is always important but it becomes even more important if the antiquity does not have a strong provenance. Sending photos of the antiquity to an archaeologist, scholar in the field, or a dealer who regularly examines such items to verify the item has the correct attributes is an important step.