Hammond - State investigators confirmed Friday the glittery substance reported in a Robertsdale neighborhood this week is different from the particle common in the steelmaking process called kish graphite.

Investigators from the Indiana Department of Environmental Management confirmed the substance is a metallic, magnetic flake. Hammond officials initially believed the substance could be kish graphite.

IDEM spokesman Dan Goldblatt said it's unknown what exactly comprises the material, so the state can't say for sure if it's toxic or not, though there have been no reports of people becoming ill.

Additional samples of the substance were gathered Friday, and IDEM intends to release a more detailed analysis in the coming days. Goldblatt said the source of the release is unknown but is likely from industry.

The city notified IDEM earlier this week when residents near the 1500 block of Brown Avenue began reporting a black and silver glittery substance in yards and on vehicles and outdoor furniture.

Hammond forwarded the complaint to IDEM because industrial sources are under the state's control, said Ron Novak, director of the Hammond Department of Environmental Management.

In the past, Novak has seen a combination of kish graphite and metal coming from local steel mills.

"Whether or not it's metal flake, or whether or not it's graphite, I think it's coming from the same source," Novak said.

"Basically there's two major industries in that area. One is steel, and one is oil," he said. "I don't believe the oil folks are involved in this. Steel mill related would be likely the first place to go."

Novak encouraged residents to notify the Hammond department if they see the glittery substance to help pin down the source of the release. Call the department at (219) 853-6306.

From a human standpoint, the material is not a major problem because the particles are large, Novak said. However, the material can embed into a vehicle's paint and cause rust spots to form.

"It's not from the car, but this material breaking down," Novak said, "and that disturbs many individuals out there."

Novak said he hopes the complaints spur an immediate and thorough investigation by the state into the source of the particles.

"This is easily captured material," Novak said. "Usually the problem in the industry is capturing superfine particles."