How much value is a dental crown/cap of porcelain fused to high noble white gold vs.fused to high noble metal?

I don't know if the cost of white gold outweighs the benefit.

How much value is a dental crown/cap of porcelain fused to high noble white gold vs.fused to high noble metal?
There is zero difference. Most porcelain fused to "high noble" crowns are on a white gold unless the dentist specifies a type of crown that uses a yellow gold. For high noble, the gold content is at least 50%, but in some cases it is over 75%. Most of the non-gold content is still high noble, such as platinum and/or palladium, which are both usually worth more than gold.