 The gills of the mushroom range from <unk> ( squarely attached to the stem ) to slightly <unk> ( running down the length of the stem ) , and crowded close together . Their color is an indigo blue , becoming paler with age or staining green with damage . The stem is 2 – 6 cm ( 0 @.@ 8 – 2 @.@ 4 in ) tall by 1 – 2 @.@ 5 cm ( 0 @.@ 4 – 1 @.@ 0 in ) thick , and the same diameter throughout or sometimes narrowed at base . Its color is indigo blue to <unk> or grayish blue . The interior of the stem is solid and firm initially , but develops a hollow with age . Like the cap , it is initially sticky or <unk> to the touch when young , but soon <unk> out . Its attachment to the cap is usually in a central position , although it may also be off @-@ center . Fruit bodies of L. indigo have no distinguishable odor . 
