Here’s the recipe for stone #3 from this post.
I used fingering/4-ply wool and 2.25mm / B hook. The stone was 7 cm ( 2.8 in) in diameter
This “jacket” is made of two motives, second joined as-you-go to the first one.
I like my “jackets” to fit really tightly over the stones. I put my work against the stone very often to make sure it’s coming out the right size.
Side1.
With green, start with a magic loop.
Round 1 – ch3, 15 dc. Finish the round with a sl st in the 3rd ch.
Round 2 – ch6, *sk 1 dc, sc in the next dc, ch 4* 7 times. Join the round with sl st in the 2nd ch from the beginning of the round.
Round 3 – ch7, *sk ch4 sp, sc in sc, ch 5* 7 times. Join the round with sl st in the 2nd ch from the beginning of the round.
Round 4 – ch8, *sk ch5 sp, sc in sc, ch 6* 7 times. Join the round with sl st in the 2nd ch from the beginning of the round.
Round 5 – ch9, *sk ch6 sp, sc in sc, ch 7* 6 times, ch 2, trbl in the 2nd ch of ch9 at the beginning of the round.
Round 6 – ch10, *sk next sc, sc in ch7 sp, ch 8*. Join the round with sl st in the 2nd ch from the beginning of the round.
Round 7 – sl st in ch8 sp. *[dc, ch 1] 4 times in ch8 sp*, using ch3 instead of the first dc of the round. Finish the round with a sl st in the 3rd ch.
Round 8 – sl st in ch1 sp. 1 dc in each ch1 sp, using ch3 instead of the first dc of the round. Finish the round with a sl st in the 3rd ch.
Bind off, weave in the ends.
Side 2.
With orange, start with a magic loop.
Round 1 – ch3, dc 5, finish with sl st. Change colour to yellow.
R2 – *ch4, 2trbl tog (each in separate dc from the previous round), ch 4, sl st in the same dc as the 2nd trbl*. Weave in the ends that’s left from starting the magic loop and changing colours. In round 3 you will be joining both sides together. Place side 1 with wring side facing you. In the beginning work with just two sides of the “jacket” held together. Once you are about 2/3 through the round, insert the stone and continue working. Remember to have all ends weaved in before starting to join the sides together.
R3 – start with 4 sl st in 1st ch4 to “go up” the cluster, ch1, *sc in 2trbl tog, ch 2, sl st in every 4th dc from side 1, ch 2*. Finish the round with sl st into first ch1. F/O and weave in the last end.
Here’s a link to tutorial on how to join elements with sl st.