During Chapter 9 (Riverside Institute) in Call of Cthulhu, one of the heroes, Aldernon Drake, will ask the protagonist to find an occult amulet that is supposed to help in the fight against the Shambler, a monster with which the player struggles during Chapter 6. The game does not give any guidelines where to look for it, offering only a picture of the bust, which is a guideline. In this chapter, you will learn how to find this amulet.
As mentioned, Aldernon Drake will offer you a tip - a photo of a bust to help you locate the amulet. There are at least a few busts here, but if you go upstairs to the Hawkins family residence and get to Sarah's room (you will recognize it by a huge occult circle drawn on the floor), you will find it. There will be a reconstruction here.
Activate the reconstruction and examine the mark on the ground, the easel, the canvas on the easel, the book lying on the ground, the circle drawn on the floor, the figure of Sarah Hawkins. Then, complete the exploration by checking the object lying at the door to the room. Leave the reconstruction mode now and go to a desk in the corner of the room. There you will also find the bust you are looking for, at the same time getting the item Sketch of a still-life.
The object in question is simply a photo where you can see the image of the next bust. You will find them next to the place where the hero woke up at the beginning of this location - on the first floor, between libraries, not far from Officer Bradley sitting at the table. Go near the sofa from which the hero stood up and approach the bust standing in a small recess in the wall. The hero will automatically collect the amulet lying there - R'lyeth Key - which you are looking for. Collecting an item will automatically raise the level of Hero's Occultism. Now you have to go back to Aldernon Drake and hand over the finding to him.