# Minimum coordinates of all vertices on each axes
	#
	# This is a corner of the bounding box.
	var min: Point3d[Float] is lazy do
		var mx = inf
		var my = inf
		var mz = inf
		var i = 0
		while i < vertices.length do
			mx = mx.min(vertices[i])
			my = my.min(vertices[i+1])
			mz = mz.min(vertices[i+2])
			i += 3
		end
		return new Point3d[Float](mx, my, mz)
	end