DENVER (CBS4) – Denver police are looking for a pair of violent thieves who were dressed up like clowns when they held up a jewelry store at gunpoint on Wednesday.

The crime happened in the morning at Sonny’s Rocks on Colorado Boulevard, and it has an unusual twist in that the most of what was taken isn’t very valuable and can easily be replaced.

Surveillance video obtained by CBS4 shows the robbers roughing up employees and even pointing a gun at one of the store’s owners.

The robbery lasted for about 15 minutes, and owner Mark Allen said one of the men “had his gun pointed to me, at one point at my head, at my neck and at my back.”

The men were wearing heavy makeup and wigs and forced the owners to unlock each of their cases in the showroom.

Mike Nedler, another owner, said the men were “pretty thoroughly disguised.”

“It’s scary, especially because the whole time they are screaming at you,” Allen said.

The robbers then put the jewelry inside into garbage bags.

PHOTO GALLERY: Surveillance Images Of The Robbery At Sonny’s Rocks

Police suspect the robbers assumed the jewelry store was full of valuable metals and precious gems, but their loot was probably not what they were expecting.

Allen and Nedler told CBS4 that because the price of the precious metals featured in their jewelry has gone up significantly, what customers see in their store — and in most jewelry stores — is usually an inexpensive sample of what is ordered from the designer. The owners said that what the robbers stole is basically worthless outside the store.

“A lot of (what was stolen) are samples that are done in silver and they are plated, and the robbers don’t know that,” Nedler said. “You don’t want to get killed over anything, but especially if it’s not real.”

The store owners say they hope to be back to business as usual on Thursday, although they remain rattled by what happened.

“It just made it kind of weird, you know, because when you look up and there’s these two guys in clown makeup and costumes, the first thought is ‘Is this for real?’ And you learn very quickly it’s for real,” Allen said.

Denver detectives told CBS4 the face paint the suspects used was so heavy it made it very difficult to determine the race of each one, though it was later determined the suspects were both African American.

Sonny’s Rocks is a long time Denver jewelry store that specializes in bridal jewelry.

Anyone with information that might be helpful to police about the crime is asked to call Denver police.