Kelvin Cheung, Director and Senior Numismatist in our Hong Kong office, is one of the hobby’s foremost experts in world paper money and Asian coins. Cheung’s expertise is well known in the numismatic community world-wide, having spent nearly the past decade at Spink, most recently as its Global Head of Banknotes and Bonds. He is highly respected among his peers and collectors.

Cheung first became interested in coins and banknotes as a child in the early 1990s, when his parents gave him foreign coins and currency that came into their fish and chip shop in the United Kingdom. His interest grew throughout his teenage years and while he pursued his education in London, dabbling in part time dealing along the way. In 2006 he started cataloging part time for Spink’s Hong Kong auctions, becoming a full time employee in 2013, a position he held through 2022. During his time at Spink, Cheung was a key contributor to the firm’s significant growth in Asia. Cheung is a member of the International Bank Note Society and the International Bond and Share Society, among other industry affiliations.

Nirat Lertchitvikul has been a major force in the Asian coin and paper money market since becoming a full-time numismatist in 1979. He has traveled extensively, seeking rarities from China, Hong Kong, Thailand, Straits Settlements, Korea, and other Asian countries, aided by his vast numismatic knowledge and his ability to communicate fluently in several languages.​

Over the past two decades, Ping Lertchit has traveled across Asia as one of the leading female numismatists,
bringing her expertise to collectors across dozens of countries and executing the sale of some of Asia's top collections. 

Using her vast knowledge of Asian history paired with her fluency in many languages, she is a premier expert in both

the numismatic industry as well as the development of the hobby. In 2020, she was a key player in the record breaking 10 year anniversary SBPHK auction.

Crystal is a certified multilingual translator and interpreter and is fluent in Cantonese, Mandarin, English and Japanese. She earned a Bachelor of Arts degree in languages from the University of Hong Kong and worked in sales at the Tokyo-Mitsubishi UFJ Bank. From there she trained with Stack’s Bowers Galleries in the field of numismatic auctions and has been an integral part of the firm’s expansion in the Asian market. Her superb customer service skills have been invaluable to our bidders and consignors alike and she is a dynamic presence on site at our auctions and conventions in Hong Kong.

Frederick Yow is a Consignment Director based in Singapore and serves clients in Singapore, Malaysia, Brunei, and Indonesia as well as greater Asia. Fred's interest in numismatics started early as a schoolboy, collecting world coins from travelling sailors. In 1993, he was introduced to the world of paper money and has been an avid collector ever since. A notable milestone of his numismatic journey was the acquisition of key "Private Bank of Singapore" notes from the famed Dr. Chan Chin Cheung Collection in 1996. He has served as co-writer and editor of "Banknotes of British Malaya, The Frank Goon Collection" published by Spink. This notable work was selected as the International Bank Note Society (IBNS) Book of The Year in 2012.

Zhou Shou Yuan, who had been collecting stamps and coins since the 1990s, joined Stack’s Bowers and Ponterio as a Numismatic and Information Technology Consultant in Mainland Ch​ina in September 2015.

In 2013, Zhou Shou Yuan founded Shouxi.com, to serve collectors interested in Chinese coins. Shouxi.com provides timely, comprehensive, authoritative and independent third party information and services, including news, archives, forums, agent bidding, consignment, shopping and more.

Shouxi.com has co-hosted a series of International Coin Expositions and other large coin events and has cooperated with 40 coin companies and associations worldwide. Shouxi.com is the most influential brand among online and offline interactive platforms in Chinese numismatics.

Zhou Shou Yuan is a graduate of the Wuhan University Electrical Engineering College, with expertise in electric power training, news reports, media relations, consulting, and more. He has 15 years of cross-industrial and management experience and a very strong relationship with Internet, print and television media.​