High quality unweathered rock, generally used in railway lines, complies with Kiwirails specification.
Winstone Aggregates track ballast conforms to the new Ballast Track Specification 140, tested by our IANZ laboratories every 1000m3. At agreed upon intervals the test reports are distributed to assist with certification requirements. The latest technology crushers are used to produce track ballast that has an angular shape with hard corners and dimensions that are comparatively equal so that the particles can sufficiently interlock to inhibit track movement and provide appropriate distribution across the sleeper load.
Contamination, segregation and degradation of the material is prevented by storing the ballast in certified stockpiles and only handling it in certain conditions.