The Canada-based group said the aims is to pay the facility off entirely by the end of the 2013 through a more aggressive repayment schedule.
Norman Williams, Rambler's chief financial officer, added: "This payment demonstrates Rambler's commitment to paying off its debts.
"With the winter season now behind us, we are beginning to see increases in the amount of high grade copper concentrate produced from the operation.
"With further incremental operational improvements we are optimistic that more free cash flow can be generated, allowing us to be more aggressive with our debt repayment schedule."
The payment of C$500,000, made yesterday, reduces the outstanding facility with Sprott to C$6.5 mln.
Rambler started production from its Ming mine last year and recently posted a maiden profit.
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