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http://www.bury.gov.uk/CHttpHandler.ashx?id=4013&p=0

Specifically discussing Moslem burials, offers :

Types of graves available

Timber, brick or concrete vaults

On request, graves will be lined with timber, brick or concrete breeze blocks to form an inner shell in the grave space. Please note that we require the following notice for these types of vault.

And in NY (http://www.isnf.org/Documents/GuideToMuslimFuneralsInWestern...) you are charged extra for not having a lining on the grave.

"A concrete or other permanent outer burial container is not required, but there is an additional charge for a burial without an outer burial container."