Military specialists using high-technology equipment for finding human remains began a search Saturday for a long-lost time capsule that was buried more than a century ago by King Kamehameha V.

The search with ground-penetrating radar began a day before the 175th anniversary of the birth of the monarch, who was the last direct descendant of Kamehameha the Great to rule the Kingdom of Hawaii.

Even if the specialists find the capsule, they won't recover it — the capsule is believed to be buried beneath the Aliiolani Hale building in downtown Honolulu, which is on the National Register of Historic Places.

"It would be pretty catastrophic for the building" to dig it up, said Matt Mattice, executive director of the King Kamehameha V Judiciary History Center.

Historians know the time capsule was buried Feb. 19, 1872 — more than two decades before the kingdom was annexed by the United States — and that it contains priceless pieces of the islands' history.

It was buried during a celebration where Kamehameha V laid the cornerstone of the Aliiolani Hale, the first building in the islands to place under one roof all the government offices, from the Legislature to the Hawaii Supreme Court.

The small casket is believed to be beneath heavy concrete slabs on the building's northeast corner, but its exact location is unknown.

It contains photos of royal families dating back to Kamehameha the Great, Hawaiian postage stamps, a constitution of the Hawaiian Kingdom, 21 Hawaiian and foreign coins, 11 different local newspapers, a calendar and books, such as a Hawaiian language dictionary.

"It sort of shows us what they thought was important at the time," Mattice said.

The purpose of the search, conducted by members of the Joint POW/MIA Accounting Command, is to determine the capsule's location in hopes of keeping it preserved, he said.

Aliiolani Hale, with the famed gold-leaf statue of Kamehameha the Great in the courtyard, is one of the most photographed spots in Hawaii.

Completed in 1874, the building was the site of rallies, political strife, an insurrection, the Massie Trial of the 1930s, which highlighted racial tensions, and the 1893 overthrow of the Hawaiian monarchy.

Aliiolani Hale was costly to build and controversial because of its location and size, among others reasons.

Today, it is dwarfed by high-rise buildings and houses the Hawaii Supreme Court, a law library and the Judiciary History Center.