See Us at:
Manufacturing Jewelers & Silversmiths Association Expo in New York, The Basel Fair, the Hong Kong Jewellery & Watch Fair and other major jewelry manufacturing fairs worldwide.


Castaldo® natural rubber products, which include
White Label®, Gold Label® and No Shrink Pink®
jewelry molding rubber in a variety of convenient
sizes and forms, are made from the latex sap of
rubber trees grown on plantations in the rain forests
of South East Asia.

The sap is collected daily from each tree
in a small cup.

Other Castaldo® rubber molding products, such as our Super High Strength™ and Econosil® silicone molding rubber and LiquaCast® liquid rubber, are based on man-made products produced by the chemical industry.

Castaldo® products are manufactured in our new factory in Franklin, Massachusetts, located between Boston and Providence, R.I.


Castaldo® has been a major part of jewelry casting since the industry's beginnings in the late 1940's.

Dr. Ferdinand E. Knight applied the scientific training he had acquired as a medical student in Vienna, Austria before World War II to the new field when he arrived in the United States as an immigrant in 1938. His father, Dr. Leon Knecht, had been a dentist in Vienna and also ran a dental supply house there. During that period the techniques of dental casting, still practiced today, were first developed.

Ferdinand Knight was one a handful of pioneers who adapted dental casting techniques to the mass production of jewelry by the lost wax casting method. For many decades he was a jewelry designer and contract caster in New York City and one of the small handful of craftsmen during that era who could cast platinum successfully.

The company grew with the casting industry and currently is the world's leading producer of jewelry molding rubber products for lost wax casting.

If you'd like a printed copy of our catalogue, or would like to send us a message or ask us a question, please write, call or fax us at:

120 Constitution Boulevard
Franklin, MA 02038 U.S.A.
Phone: 508-520-1666
Fax: 508-298-0160


Copyright © 1991-2018 F. E. Knight Inc. ALL RIGHTS RESERVED