Natural Stone Institute 2020 Board of Directors


Robert Zavagno

Robert Zavagno

Cleveland Marble Mosaic Co.
4595 Hinckley Industrial Parkway
Cleveland, OH 44109
Phone: 216.749.2840


Mike Picco

Mike Picco
Vice President/President-Elect

PICCO Engineering
8611 Jane Street, Suite 200
Concord, ON
Phone: 905.760.9688 ext 223


Greg Osterhout


Greg Osterhout
Immediate Past President
Northern Stone Supply
P.O. Box 249
Oakley, ID 83346
Phone: 208.862.3353


Badia “Buddy” Ontra


Badia “Buddy” Ontra

Ontra Stone Concepts
541 Central Ave.
Bridgeport, CT 06607
Phone: 203.367.4757


Duane Naquin

Duane Naquin

Stone Interiors East
131 Palmetto Court
Gaston, SC  29053
Phone: 803.461.8950


Herwig Callewier

Herwig Callewier
Director (2017-2021)

Beltrami Natural Stone
Benetielaan 22, Harelbeke, VL
Belgium  B-8530
Phone: + 32 56 23 70 00
Zone 10: Europe


Evan Cohen

Evan Cohen
Director (2019-2022)

Quality Marble & Granite
731 South Taylor Avenue
Ontario, CA  91761
Phone: 909.983.0655
Zone 7: Alaska, California, Hawaii, Oregon, and Washington


Leonardo De Tatagiba

Leonardo De Tatagiba
Director (2018-2021)

Granitos Zucchi
Av Jacaraipe, 1423 – Jacaraipe
Serra ES,  Brazil 29173-392
Phone: +55 27 3243 9666
Zone 9: Central & South America, Mexico, Puerto Rico, and the Caribbean


Jeff Erickson

Jeff Erickson
Director (2020-2023)

Cutting Edge Countertops
1300 Flagship Drive
Perrysburg, OH 43551
Phone: 419.873.9500
Zone 4: Midwest: Iowa, Indiana, Illinois, Kentucky, Michigan, Missouri, Ohio, and Wisconsin


Mariavittoria Grassi

Mariavittoria Grassi
Director (2018-2021)

Grassi Pietre srl
Via Madonetta, n 2
Nanto VI, VIItaly 36024
Phone: +39 329 4386100
Zone 15:  At-Large


Katie Jensen

Katie Jensen
Director (2019-2022)

Triton Stone Group
6131 River Rd.
Harahan, LA 70123
Phone: 504.738.2228
Zone 5: South Central: Arkansas, Louisiana, Mississippi, Oklahoma, and Texas


Ali Kader

Ali Kader
Director (2017-2022)

Egy-mar International
LOB 09 Office No. 115 Jebel Ali Free Zone
P.O. 18382 Dubai,  United Arab Emirates  18382
Phone:  +20 12 23 19 21 02
Zone 11:  Africa and Middle East


Bruce Knaphus

Bruce Knaphus
Director (2016-2020)

KEPCO+, Inc.
4190 South Highland Drive
Suite 112
Salt Lake City, UT 84124
Phone: 801.975.0909
Zone 6: Rocky Mountain: Colorado, Idaho, Kansas, Minnesota, Montana, Nebraska, Nevada, New Mexico, North Dakota, South Dakota, Utah, and Wyoming


Jonathan Mitnick

Jonathan Mitnick
Director (2020-2023)

CCS Stone, Inc.
9-11 Caesar Place
Moonachie, NJ 07074
Phone: 201.933.1515
Zone 2: Mid-Atlantic:  District of Columbia, Delaware, Maryland, New Jersey, North Carolina, Virginia, and West Virginia


Marcella Prado

Marcella Prado
Director (2018-2022)

Laticrete International
1700 Montrose Ln.
Lincoln, CA  95648
Phone: 203.859.2069
Zone 13: Associate Members


Josh Zhang

Josh Zhang
Director (2018-2020)

Jianming Stone Group
Unit 14 C109, Zhenhua Building, Dongdu Road, Xiamen, China
Phone: +86-13806020460
Zone 12: Pacific Rim: Asia, Australia, and Philippines



Board Nominations

Nominations Open Spring of 2020. Click for more information.

If you are interested in serving or know someone interested in being a board member candidate, please contact the Natural Stone Institute CEO, Jim Hieb.

Natural Stone Institute Executive Staff

Jim Hieb, CAE
380 E. Lorain Street
Oberlin, OH 44074
Phone: 440.250.9222
Fax: 440-774-9222

Executive Vice President
Jane Bennett
36 Cougar Lane
Chestertown, NY  12817
Phone: 440.250.9222
Fax: 440-774-9222


Professional Staff at Natural Stone Institute Headquarters

Technical Director
Chuck Muehlbauer
5743 Spruce Street
St. Cloud, Minnesota 56303

CEU Administrator
Naomi Kocer



Stones of North America

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