If the Swansea Bay Tidal Lagoon marine energy project gets the go-ahead then millions of tonnes of armour rock could be quarried and shipped out of Dean Quarry on the Lizard.
Cemex who own Dean quarry closed it down in 2005 with the loss of 15 jobs. Up until then the quarry shipped millions of tonnes of roadstone to south coast ports.
A construction firm is investigating and evaluating a scheme that would see the old steel jetty at Dean quarry demolished and replaced by a 600 metre long breakwater to berth two ships.
The company wants to reopen Dean near St Keverne as early as next year and says it hopes to extract at least 1.5 million tons of material in the first year alone.
Liz Marsden, of Shire Oak Energy Limited, said if it received planning approval, the quarry could be reopened as early as next summer.
The current jetty at Dean which served the quarry for decades was a tidal berth.
Cornwall Council and the Marine Management Organisation will have to be consulted.
In order to berth ships alongside at all states of the tide a much longer jetty is necessary to find the deeper water.
One thing is for sure in a full easterly storm the berth and equipment need to extremely robust to withstand the heavy seas.
The rock will be shipped to south Wales and used to create an enormous breakwater for a tidal lagoon off Swansea. Taking three years to build and using five million tons of rock, it will harness the tides and generate renewable energy.
The total length of the lagoon wall is 10 kilometres and the bund is 9.5 kilometres.
She added that other possible quarries with a licence and the right kind of rock were in the Netherlands or Norway.
Before any work could go ahead, the plans for Dean Quarry would need to secure the approval of the government's Marine Management Organisation and Cornwall Council.
The reopening of the quarry could also be good news for Falmouth, as before its closure in 2005 it was reported to represent about eight per cent of pilotage movements for the towns pilots.