This heart is 3D printed and when put in the sandtray the sand shows through. It comes in two sizes. The medium size is 4.5 x 5 inches so a few small miniatures could be put in each side. The small version is made specifically for those who need an economical and accessible option for sandtray miniatures. If space on your shelves is an issue, this broken heart can also help at 1.75 x 2 inches.