A band saw found in the home of a man who worked with Robert William Pickton was covered in yellow, fatty material, the jury at Pickton's murder trial was told Tuesday.

Civilian lab technician Tanya Dare testified she spent a great deal of time examining the saw belonging to Pat Casanova.

Casanova, who helped Pickton with his pig butchering business in Port Coquitlam, B.C., was arrested in 2003 along with two other people, Dinah Taylor and Lynn Ellingsen. None of the three was ever charged.

Pickton was arrested a year earlier and charged with the first-degree murder of 26 women who disappeared from Vancouver's Downtown Eastside. Pickton is currently on trial for six of the murders, and will face another hearing at a later date.

Dare told the jury in B.C. Supreme Court in New Westminster that she examined the saw for substances like blood and protein. Her testimony Tuesday did not discuss the results of her tests.

Defence lawyer Richard Brooks questioned Dare about her examination.

"You spent a considerable amount of time visiting this particular exhibit, to the extent you went back on two separate occasions," he suggested to Dare.

She agreed, noting there was a great deal of fatty material on the saw.

Jurors spent a good part of the day listening to technicians run through a long list of the evidence they found in connection with the case. They testified to how they examined each piece and what they were looking for, but have not yet told the court about the test results.

Evidence contaminated, court told

Two of the technicians who testified Tuesday admitted they contaminated some of the evidence with their own DNA, the jurors were told.

Jorge Frasca admitted his DNA was found on a headboard and on a gun that had a sex toy attached to it. Nancy Eng, another technologist, said her profile was found on five pieces of evidence.

Pickton is on trial for the murders of Marnie Frey, Brenda Wolfe, Mona Wilson, Georgina Papin, Sereena Abotsway and Andrew Joesbury. He has pleaded not guilty to all 26 charges.

With files from the Canadian Press