I find when working with a stone like Portland its really important to think about creating strong shadows as you don’t have veins or contrasting colours like on marble. Here I am trying to create nice crisp junctions where the roots meet the edge of the disc. This helps create strong contrasts between light and shadow helping to lead the eye around the forms. I use a fine marble point chisel to remove the waste stone as this has very little risk of breaking anything accidentally and then work over with flat chisels and a claw again for the inside edge of the disk.
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