Synthetic graphite is significantly more expensive to make but commands the highest market prices due to its purity. It can cost $4000 - $5000 per tonne (99.5% purity) to produce but can be sold for $7000 - $9000 per tonne. Ultra-high purity (99.9%) graphite can demand a price of $20,000 - $30,000 per tonne. Processing and purification of natural graphite has improved greatly in recent years and projects with initial high purity graphite, like the Albany vein-type, require less purification and therefore lower cost to produce.
The man with no brain was foaming at the mouth when I mentioned $20,000 it must be terrible for him to see $30,000 in this message :ROFL