Sawn sandstone and limestone should be sealed. We always recommend it. Even more so where the colour is very light, as it is with, for example, Beige Sawn Sandstone.
This is because sawing opens up the pores in the stone and makes slabs more absorbent. Sealing repels water, reducing staining and making cleaning easier.
To find out more about when and why we recommend sealing, see the link at the bottom of this post.