Monday, June 7, 2010
Largest piece of chalk - Bishop
Canevin students sets world record
PITTSBURGH, PA, USA -- Terry Dougherty,
Matt Durbin and Nick Sylvester, 11th-grade students
Canevin High School, made a 270 pounds piece of chalk
from plaster of Paris and water , setting the world record for the Largest
piece of chalk.
Photo: Terry Dougherty, with classmates
Matt Durbin and Nick Sylvester behind him, checks the weight
of the Largest
piece of chalk in The World they made for history
teacher Joseph Romano at Bishop Canevin High School. Photo
by Darrel Sapp
"[The World's Largest
piece of chalk ] writes and everything," Mr. Sylvester
said. "But it's 270 pounds, so it's pretty hard to write with."
Typical blackboard chalk is manufactured from
gypsum, which is a kind of calcium sulfate. Sidewalk chalk
is also manufactured from gypsum, but it can be made from
plaster of Paris and water, the method chosen by the Bishop
Nick Sylvester of Kennedy wanted to make
the World's Largest
piece of chalk in a 32-gallon trash can, and so he
purchased enough plaster of Paris to fill the can more than
halfway up. He bought 125 pounds of plaster from Home Depot
for around $60.
Working with classmates Matt Durbin of Robinson
and Terry Dougherty of Crafton, he mixed the plaster with
14 gallons of water in the trash can.
It took them about 15 minutes to adequately stir
the mixture using a golf club and a metal rake, and it took
three days before the mixture set.
The World's Largest
piece of chalk is white, weighs about 270 pounds,
and looks much like a normal piece of chalk except for its
unusually large size and the patterning caused by grooves
in the trash can.
To compensate for their time and
effort, Mr. Romano will give the boys 15 to 20 extra credit
Meanwhile, the Largest
piece of chalk in The World has found a permanent
home in his classroom. "I'll probably chip away at it," Mr.
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Related world records:
rubber band chain - Allison Coach
Concrete Gnome - Iowa State University
gum wrapper chain - Gary Duschl
string of beads - Shipwreck Beads
Ball of Paper - nrique Miramontes and Ricardo Granados
rubber band ball - Joel Waul
Ball of Plastic Wrap - Jake Lonsway
Monday, June 7, 2010