As the world awaits the preliminary results of Michael Jackson’s autopsy, the details surrounding his mysterious and sudden death remain shrouded in rumor and speculation.

The L.A. County coroner began the pop star’s autopsy Friday morning in an attempt to determine the cause of death and whether prescription drugs played a role in his untimely demise.

Procedures done during an autopsy can vary depending on the circumstances surrounding the death. In Jackson’s case, toxicology tests could delay the results for weeks.

"We'll be performing toxicology tests and an extensive exam and it could take up to six to eight weeks before we have the final results," Los Angeles county assistant chief coroner Ed Winter said in a press conference Friday.

“The coroner will be looking for any natural reason for death and any indication that drugs may have caused or contributed to his death – and usually, the latter is the case,” forensic pathologist Dr. Michael Baden told FOXNews.com.

Baden, whose been involved in high-profile autopsies like that of Anna Nicole Smith, and more recently performing a second autopsy on actor David Carradine, said one of the most important things is to take samples of blood, urine and bile.

“Then they’ll check stomach contents — to see if any pills taken were by mouth,” he said. “The liver also gives a lot of information because most drugs are processed in the liver.”

All of these samples will then be saved for the toxicologist.

But before any of those samples are taken — the first thing coroner’s office does is to make an official identification. Then they’ll do an external exam where they’ll be looking over the body for scars, tattoos, birthmarks or any other identifiable markings, Baden added.

“The most common reason for a 50-year-old to die is due to heart disease, brain disease or lung disease,” Baden said.

“An internal examination will tell right away if there’s anything like an aneurysm or hardening of the arteries — that’s easily seen with the naked eye,” Baden said. “Then they’ll take tissue samples that are looked at under a microscope, which takes a couple of working days.”

In 90 percent of autopsies done in medical examiners office, the cause of death is put on the death certificate the same day. In cases where toxicology is needed, depending on priority, it can take anywhere from a couple of days to weeks, Baden added.

In the meantime, Jackson’s family will be able to make funeral arrangements while the tests are still being done.