I ended up trying four sizes of hook.  First my favourite is the 8mm aluminium It gave a firm texture, which would be fine for a rug or placemat.

Second is a 10mm hook.  The texture if this is coming out feeling good, not too tight with a bit of flexibility. 

The third one is a 12mm knooking hook. The texture of this initially came out feeling very soft, but a bit loose and slabbery.  However, as I carried on, my tension evened out and become tighter.  Hence the fourth hook.

The fourth hook is a 15mm.  I liked the result I got from this best of all.

So here are my stitch and row counts from a 10 x 10cm square (4″ x 4″) for the four hooks, and photos in a gallery for you.

8mm hook –     8 stitches, 10 rows

10mm hook –   8 stitches, 8 rows

12mm hook –   7 stitches, 9 rows

15mm hook –  7 stitches, 7 rows.

In searching for a project to use this yarn for I found a crochet version of Claire’s Outland Cowl on Ravelry. I rather like this.

The link for it is here.

https://www.ravelry.com/patterns/library/outlander-claires-cowl-crocheted

I have 650g of super chunky in my yarn stash, which has languished unused for too long, so decided to exlore what I can do with it, or whether I want to pass it on.  I tried it out as a first round of a granny square, and it looks good.  I like the nubbly texture it has

So now to try and work out what size of hook to use and how far it will go by doing a test square.  The recommended hook size is 10mm.  I know that I tend to work tightly, so a looser hook might be better.

I always make a test square bigger than the 4″ x 4″ (10cm x 10cm) recommended.  This means that I can lay a 4″x4″ cut out square on top of the test piece and count the stitches and rows, without pulling the work out to “fit” the ruler, and getting a false reading.

I am trying three sizes of hook, because I have these immediately to hand.  First my favourite is the 8mm aluminium but see immediately that this is a bit small for the yarn.  It gives a firm texture, which would be fine for a rug or placemat.  But that is not what I want.  Still will continue for comparison.

Second is a 10mm hook.  It’s actually a knooking hook, but I like this one as it is polished wood, not bamboo.  I did try a bamboo hook, but it isn’t as smooth and didn’t move as easily through the work, so I didn’t like the snaggy feel as I worked with it.  The texture if this is coming out feeling good, not too tight with a bit of flexibility. 

The third one is a 12mm knooking hook. The texture of this is coming out feeling very soft, but it looks a bit loose and slabbery, so don’t think this will end up being the best.  We shall see.