1 diamond block = 9 diamonds 1 layer of res = 3600 blocks 1 res = 255 layers 9x3600x255=8262000 diamonds in rupees 8262000x45=371,790,000r
Diamonds have not been 45r for a very long time. The days of 40r diamonds, around the same time SMP5 was known well as the coolest server ever, have long passed.