Tunisian astounds me at every turn - it seems as though any technique you can find in knitting or regular crochet can be replicated with Tunisian crochet! And, so it is with mosaic. What a wonderful discovery! With the help of Richard Gartland's free pdf on the Advanced Tunisian Crochet group on FB, I learnt a new skill that makes me very happy!
The greatest thing about Tunisian mosaic is that, even though you are working one Tunisian row per colour (actually 2 rows, a forward and return pass) you never have to cut the yarn at the end of the row like with overlay mosaic as the yarn lands up back where it started and is just carried up the side, just like with inset or 2 row mosaic.
Another benefit is that you can use any regular crochet overlay mosaic graph. Where one would do a mosaic dc, you would substitute it with an extended front post TSS (Tunisian simple stitch) into the same colour 2 rows below. Any Tunisian stitch is extended simply by adding a chain, once the stitch is completed. Where you would do a scblo (single crochet in the back loop only), you would do a TSS. Your loop on the hook at the beginning of your FP counts as your starting sc (in regular crochet) and you would end of the FP (forward pass) as always, going through both loops of the last stitch.
It is sometimes a bit tricky to find both loops required to do your extended FPDC, but I have found having a longer nail on my index finger helps me to separate the stitches and find the front and back legs of the stitch. It is also, therefore, much easier to use 2 contrasting yarns, as it is easier to see the stitches. My first attempt was using a solid and a self-changing yarn, which initially worked very well, but when the colours started becoming very similar, not only was it difficult to find the stitches, but the design also got lost and I abandoned the scarf I was making. Below you can see why.
If the self-changing yarn nowhere came close to the solid yarn colour, it would work well as happened with the beginning of the scarf. Well, lesson learnt! Should have clicked earlier!
