She's very cautious as she reaches out and takes the mask from him. There's a very obvious relief in her features when no vision appears as she turns it over in her hands. The magic going on here doesn't make sense to her, but, for once, she's grateful for its use.

"Thank you." There isn't any good follow up to that and she knows it. Instead she asks, "How much do I owe you for the mask?" It's easier for her to focus on things she understands, like prices and haggling.