I purchased this new, but it has been stored without use. The crystals change according to changes in the weather. It's stylish as an interior decoration and also interesting for children's weather observation. There are white streaks on the inside of the glass. These are from the initial production. I've attached photos, but they are not noticeable from a distance. However, those who are overly concerned with cleanliness may want to refrain from purchasing. Please ask any questions before purchasing. bitten object weather station science project