Using the same marble on the splashback would be perfect. I actually think it would be too much if you introduced another finish into the scheme. If the budget allows I would definitely match the splashback to the benchtop.
It really depends on your personal preference. I personally think that a splash back that is different to the marble island would be suitable! Have you thought about frosted glass or even a tinted mirror splash back? They do add value and can also be a great focal point in any kitchen. :-)
The Interior Difference
Fiona Anastasia Whitefoot
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