Our company has five types of Vratza limestone: R1 and R2 could be explained as first quality material.
R1 is unique strong and homogenous material, which is almost snow-like surface with creamy-beige pattern and smallest possible inclusions of quartz dots.
R2 is also strong and homogenous material with several quartz spots (not too big) on a clean creamy-beige base.
R3 limestone has a lot of small to middle size quartz spots onto its surface and a few big quartz spots. It looks like a tiger skin.
R4 limestone has big quartz spots onto surface. It is very strong material, suitable for projects where you make the selection to cut-to-size elements and you are able to extract also a big part of clean material from some slabs.
R5 limestone has big quartz spots, middle size quartz spots and sometimes there is a yellow line on the slab.