How expensive was the ointment that the woman poured on Jesus’ head, and what made it so valuable?

Now when Jesus was at Bethany in the house of Simon the leper, a woman came up to him with an alabaster flask of very expensive ointment, and she poured it on his head as he reclined at table. And when the disciples saw it, they were indignant, saying, “Why this waste? For this could have been sold for a large sum and given to the poor.” NIV Matthew 26:6-9

The disciples reveal to us that the ointment used was expensive, but we do not know its exact cost. What makes the ointment so special and why is it so valuable? The ointment came for Northern India and was made of pure nard. The worth of the ointment was about a years worth of wages. Nard is made from a plant that grows in the Himalayas and is used as ointment or perfume. The cost of the ointment was worth…