SACRAMENTO, Calif. — The identity of the person whose Mega Millions ticket is worth half the $648 million jackpot remained a mystery Friday, but lottery officials said it’s not unusual for big winners to delay claiming the prize while they seek advice.

One of two winning tickets for Tuesday’s drawing was sold at a San Jose gift shop. The other was sold in Georgia and the winner already has been identified.

California Lottery spokesman Alex Traverso said the second winner has a year to claim the money.

“It’s fairly common in cases like this that they’ve hired financial representation and an attorney so they come forward with a plan of action,” he said.