To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyses reviews to verify trustworthiness.
My son loved this and it helped keep him entertained during lockdown. There are lots of stones. The information leaflet isn’t that great but we bought it for the stones so it wasn’t a problem. One type of stone is very delicate and crumbles easily.