This year, over 250 dedicated readers participated in the 2000 Gems & Gemology Challenge. Entries arrived from all corners of the world, as readers tested their knowledge on the questions in the Spring 2000 issue. Those who earned a score of 75% or better received a GIA Continuing Education Certificate recognizing their achievement. The participants who scored a perfect 100% are listed below.

AUSTRALIA Cranebrook, New South Wales: George Newman. Dodges Ferry, Tasmania: Robin Hawker. Logan, Queensland: Ken Hunter

BELGIUM Diegem: Guy Lalous. Diksmuide: Honore Loeters. Hemiksem: Daniel De Maeght. Ruiselede: Lucette Nols

BRAZIL São Paulo: Daniel Berringer, Ana Flavia Pantalena

CANADA Bissett, Manitoba: Paul Gertzbein. Bobcaygeon, Ontario: David R. Lindsay. Calgary, Alberta: Diane Koke. Cowansville, Québec: Alain Deschamps. St. Catharines, Ontario: Alice J. Christianson. Toronto, Ontario: Ken Miller. Vancouver, British Columbia: Michael Cavanagh

CROATIA Zagreb: Sandra Crkvenac

CZECH REPUBLIC Praha, Kamy’k: Karel Mavrík

FRANCE Paris: Marie-France Chateau

GREECE Thessaloniki: Ioannis Xylas

INDONESIA Jakarta: Warli Latumena

ITALY Bordighera: Beviacqua Lorenza. Caltanissetta, Sicily: Francesco Natale. Lucca: Roberto Filippi. Porto Azzurro, Livorno: Giuseppe Diego Trainini. Valenza: Rossella Conti. Vicenza: Francesca Zen

JAPAN Kyoto: Takuma Koyanagi

MALAYSIA Georgetown, Penang: Lee-Khoon Ng

NETHERLANDS Amsterdam: P.A.G. Horninge. Rotterdam: E. van Velzen. Voorburg: W. van der Giessen. Wassenaar: Jane M. Orsak

PHILIPPINES Mandaluyong City, Manila: Mark Alexander B. Velayo

PORTUGAL Figueira, V. du Bispo, Algarve: Johanne Jack. Viseu: Rui P. Branco

SCOTLAND Edinburgh: James W.M. Heatlie

SPAIN Playa P. Farnals, Valencia: Monika Bergel-Becker. Port de Sóller, Baleares: J. Maurici Revilla Bonnin

SWITZERLAND Rodersdorf: Heinz Kniess. Zollikon: Adrian Meister. Zürich: Eva Mettler

UNITED STATES Alabama Gadsden: Jerome D. Thomas. Hoover: Ronald C. Redding
Arizona Chandler: LaVerne M. Larson. Tucson: Molly K. Knox
California Burlingame: Sandra MacKenzie-Graham. Carlsbad: Michael T. Evans, Brian I. Genstel, William J. Herberts, Mark S. Johnson, Jan Lombardi, Diane H. Saito, Abba R. Steinfeld. Escondido: Martin Harmon. Fremont: Ying Ying Chow. Morgan Hill: Douglas Mays. Pacifica: Diana L. Gamez. Rancho Cucamonga: Sandy Mac Leane. Redwood City: Starla Turner. San Rafael: Robert A. Seltzer. Ukiah: Charles "Mike" Morgan
Colorado Colorado Springs: Deborah Doty. Denver: Mary Shore, Alan J. Winterscheidt. Ft. Collins: Frank Sullivan. Longmont: William Lacert. Pueblo: Naoma Ingo
Connecticut Simsbury: Jeffrey A. Adams
Florida Clearwater: Tim Schuler. Sunny Isles Beach: Fabio S. Pinto
Georgia Hampton: Ella Golden
Illinois Mokena: Marianne Vander Zanden. Northbrook: Frank E. Pintz. Oaklawn: Eileen Barone. Peoria: John Fitzgerald. Troy: Bruce Upperman
Iowa Iowa City: Gary R. Dutton. West Des Moines: Franklin Herman
Louisiana Baton Rouge: Harold Dupuy
Maine South Freeport: Arthur E. Spellissy Jr.
Massachusetts Braintree: Alan R. Howarth. Brookline: Martin Haske. Chatham: William Parks. Lynnfield: John A. Caruso. Uxbridge: Bernard M. Stachura
Maryland Darnestown: Ron Suddendorf. Potomac: Alfred L. Hirschman
Missouri Perry: Bruce L. Elmer
Montana Helena: Werner Weber
Nebraska Omaha: Ann Coderko
Nevada Las Vegas: Deborah A. Helbling. Reno: Terence E. Terras
New Jersey Hawthorne: Donna Beaton
New Mexico Santa Fe: Leon Weiner
North Carolina Creedmoor: Jennifer Jeffreys-Chen. Durham: Kyle D. Hain. Hendersonville: Robert C. Fisher. Kernersville: Dr. Jean A. Marr. Manteo: Eileen Alexanian
Ohio Athens: Colette Harrington. Toronto: Vincent Restifo
Oregon Beaverton: Robert H. Burns. Clackamas: Evelyn A. Elder. Salem: Donald Lee Toney. Scappoose: Cinda V. di Raimondo
Pennsylvania Schuylkill Haven: Janet L. Steinmetz. Wernersville: Lori Perchansky. Yardley: Peter R. Stadelmeier
South Carolina Sumter: James S. Markides
Tennessee Altamont: Clayton L. Shirlen
Texas Corpus Christi: Warren A. Rees. El Paso: Richard A. Laspada. Houston: Frieder H. Lauer
Virginia Hampton: Edward A. Goodman. Sterling: Donna B. Rios
Washington Lakebay: Karen Lynn Geiger
Wisconsin Beaver Dam: Thomas G. Wendt. Milwaukee: William Bailey