This is just something that I've made up as I've gone along, hopefully it's not too confusing!
Cast on 31 on 8mm needles, join to make 30 stitches around.
Rows 1-5: k1p1 (30st)
Switch to 6mm needles
Rows 6-10: k1p1 (30st)
Row 11: k30
Row 12: k14, k2tog, k14, k2tog (28st)
Row 13-40: k28
Row 41: k1, m1, k26, m1, k1 (30st)
Row 42-47: k30
Row 48: k1, m1, k28, m1, k1 (32st)
Row 49: k32 around
Row 50: k32, turn
making the thumbhole, at the end of each row make sure you do not join each round
Row 51: p32 turn
Row 52: k32, turn
Row 53: p32 turn
Row 54: k32, turn
Row 55: p32 turn
Row 56: k32, turn
Row 57: p32 turn
Row 58: k2tog, k28, k2tog turn (30st)
Row 59: p30 turn
after the thumbhole, join the rounds:
Row 60: k30 and join
Row 60-65: k30 around
bind off
The finished measurements are:
Length: 37cm
width at base: 24cm (circumference)
width at hand: 20cm (circumference)
I used some cotton worsted yarn which isn't widely available.
The skein I used was approximately 173.0 meters (at 200g) and I used about 137g so 119 metres for two mitts, hopefully this is accurate but should I make this pattern in a standard yarn I will state those figures too.