I checked first to make sure this product isn't sold by ProHealth. I didn't find it in my search. I've been purchasing Earthborn Products CS, but it's very expensive. I know that a good quality silver will have small particles and be crystal clear, so I'm wondering if anyone knows of a less expensive alternative-brand CS with similar quality? Earthborn runs $25 for eight ounces (16 days worth). Very expensive, but I do notice my colds have lessened severity and duration when I take it. Any help will be greatly appreciated .