In one room in the back of Taber Library, hundreds of cards spread over a large table. Each one offered a unique pattern and design.

"Pick one," said henna tattoo artist Mandy Roberge. "I can do them all."

She could not tell a lie. The small room was crowded on Thursday as the sun broke through the clouds, but Roberge sped through the tattoos quickly, no matter how small and intricate the details.

It's no small feat, but for Roberge, the owner of "Wicked Good Henna", it's just another day in the office. Roberge, out of Leominster, has been a certified henna tattoo artist for several years. "My friend bought me a henna kit, and I went a little crazy," she said with a laugh. Her business has grown every year since.

Henna, a temporary and nontoxic skin dye, is derived from the henna plant. It has been used for tattooing and decoration purposes since the Bronze Age. Roberge applies the henna paste from a tube, drawing swirling designs on her clients' skin.

Roberge found herself at the Taber Library when Children's Librarian Rosemary Grey gave her a call. "We're always trying to get teenagers into the library," Grey said cheerfully. "This was a great opportunity."

Grey was right on the money. If teenagers were what the library wanted, teenagers is what they found. The small room was consistently packed, by both teenagers and their mothers, who all left with fanciful designs covering their hands.

The process of getting a henna tattoo, though it seems intricate, is simple. The trickier part is what happens once the tattoo is done. Once complete, the mud-like mixture dries within five to 10 minutes, and will eventually flake off to reveal the dyed skin underneath. In a best case scenario, the dye can last one to two weeks.

Roberge also says that it's best to avoid water on the tattoo for the first 48 hours. "Obviously, you have to wash your hands and take a bath," she said, but told her clients to be careful and cover the tattoo with coconut oil if needed, to help deflect water.