High-Accuracy 3D Optical Profilometry for Analysis of Surface Condition of Modern Circulated Coins

• Main Authors: Wojciech Kapłonek, Tadeusz Mikolajczyk, Danil Yurievich Pimenov, Munish Kumar Gupta, Mozammel Mia, Shubham Sharma, Karali Patra, Marzena Sutowska
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Materials
• Subjects: circulated coins; surface condition; optical methods; measurements and analysis
• Online Access: https://www.mdpi.com/1996-1944/13/23/5371

The article shows that noncontact measurement techniques can be an important support to X-ray-based methods when examining the surface condition of modern circulated coins. The forms and degrees of wear of such coins, affecting their utility values, qualifying them as a legal tender in a given country, can be measured and analyzed, among other things, using advanced high-accuracy optical profilometry methods. The authors presented four analyses carried out for reverses and obverses of round coins (1 zloty, 1 franc, 50 bani, 5 pens) characterized by different degrees of surface wear. All of the coins were measured using 3D optical profilometers (Talysurf CLI 2000 and S neox) representing two generations of these types of systems. The obtained results confirm the validity of the applied high-accuracy measurement systems in conjunction with dedicated software in the presented applications. Examples of the analyses carried out can be a significant source of information on the condition of coins in the context of maintaining their functional properties (selection of appropriate wear–resistant alloys and correctness of the production process).