Answer:
Ancient effigies are dropped by many NPCs (Non-Player-Characters) to me they seem rare I have only gotten 1. The kind of effigies there are is starved ancient effigies level 91 in 1 of 2 skills and rewards 15,000 experience, nourished ancient effigies level 93 of 1 of 2 skills rewards 20,000 experience, sated ancient effigies level 95 in 1 of 2 skills rewards 25,000 experience, and gorged ancient effigies level 97 in 1 of 2 skills rewards 30,000 experience. Most players who don't have the level in the one of the skill usually goes to the grand exchange and asked to get assisted in that skill so they can get the experience for the effigy. Usually the player with the skill level will come up to that person but if the player who is trying to open the effigy has to go up to a person they see with a skillcape for that effigy and they ask for assistance. The other player player will often tell him that he is maxed out meaning he has already assisted to many people for that day.