This Memorial Day weekend is an especially sad one for metal and hard rock fans as they say goodbye to two of their favorite musicians.Private funeral services were held on Friday (May 28) in Des Moines, Iowa for SLIPKNOT bassist Paul Gray, who was found dead in a hotel room in a Des Moines suburb on May 24. The cause of Gray's death has not been determined, although according to a 911 call a hypodermic needle and pills were found near the 38-year-old musician's body. SLIPKNOT has not hinted at its future plans. A public memorial service was held on Sunday (May 30) in Los Angeles for Ronnie James Dio, the BLACK SABBATH, RAINBOW and DIO frontman who lost his battle with stomach cancer two weeks ago at the age of 67. More than 1,200 fans and friends attended the event. The deaths of Dio and Gray are the latest that have stunned the heavy rock world in the past six months. AVENGED SEVENFOLD drummer James "The Rev" Sullivan died last December, while TYPE O NEGATIVE frontman Peter Steele passed away last month. Ozzy Osbourne, who knew or had a passing acquaintance with all four artists, tells The Pulse of Radio it's sad to see so many musicians pass away in such a short period of time. "I mean, of late everyone's dropping dead," he says. "This happens every so often, you know. I'm only hoping my number don't come up soon. It's what happens, you know. You hear me talking, I'm lucky I'm not one of the dead ones, 'cause I used to — I mean, Ronnie James Dio didn't have any problems, but when there's drugs involved or alcohol...I should have died a thousand times."