Gravel Limestone Slag Sand
Indiana Mineral Aggregates Association



By definition the keystone is the topmost stone of an arch, popularly thought of as especially holding the others in place. This award recognizes an individual in the aggregates industry who has shown exceptional leadership and outstanding dedication to advance the goals, growth, and well being of the Indiana aggregates industry.

Decision Makers:

IMAA President and Executive Director (no entry form to submit)

Current Keystone Winners:

(presented at following year workshop)

1998 Ken Mulzer, Sr., Mulzer Crushed Stone

1999 David Grom, Stoneco, Inc.

2000 None

2001 None

2002 John Schuler, Martin Marietta Aggregates

2003 John Hamm, Jr., Liter's of Indiana, Inc.

2004 None

2005 Larry Brost, Stone-Street Quarries, Inc.

2006 None

2007 Ken Wanstrath, New Point Stone Co., Inc.

2008 None

2009 None

2010 Ken Rush, Sellersburg Stone Company


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IMAA members produce crushed stone, sand, gravel or slag, sell mining equipment, haul material, and much, much more.
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The Source Report – the bi-monthly membership newsletter of the Indiana Mineral Aggregates Association.

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