Riverstone Announces Update of Gold Mineralization at Karma Project

Riverstone Resources Inc. (TSX-V: RVS) ("Riverstone" or the "Company") announces an updated independent NI 43-101 compliant Mineral Resource estimate, that shows an increase of 27% for the Indicated in-pit mineral inventory and 23% for the global mineral inventory compared to the January, 2012 resource estimate at its flagship Karma gold project (the "Karma Project") in Burkina Faso, West Africa (See Riverstone's news release dated January 9, 2012). The NI 43-101 compliant resource estimate has been completed by P&E Mining Consultants Inc. ("P&E") of Brampton, ON. The estimate was completed on the Goulagou I, Goulagou II, Kao, Rambo and Nami deposits, which are all in close proximity to each other.

HIGHLIGHTS (resources are contained within five Whittle open pit shells)

• Global Mineral Inventory (inside and outside of Whittle pit shells) consists of Indicated gold mineralization totalling 2,252,000 ounces of gold in 68.8 Mt at an average grade of 1.02 g/t Au and Inferred gold mineralization totaling 1,115,000 ounces of gold in 40.4 Mt at an average grade of 0.86 g/t Au.


• A significant portion of the gold resources are at shallow depth (less than 200 metres vertical depth) and over 72% of the global mineral inventory is contained with the five Whittle pit shells.


• Total Indicated gold resources within five Whittle pits are 1,943,000 ounces of gold in 56.5 Mt at an average grade of 1.07 g/t Au.


• Total Inferred gold resources within five Whittle pits are 492,000 ounces of gold in 15.4 Mt at an average grade of 1.00 g/t Au.


• 80% of the resources within the Whittle pit shells are classified as Indicated gold resources.


• Mineralization remains open at depth and along strike in at least one direction for all deposits.


• This resource will be used as the basis for proceeding with a definitive Feasibility Study (FS) commencing in Q4, 2012 based on total Indicated resources of leachable material containing 1,030,000 ounces of gold, an increase of 24% compared to the resources used in the August 20, 2012 PEA.

"We are very encouraged with the increase of resources at Karma", commented Dwayne L. Melrose, President and CEO of Riverstone Resources Inc. "This will provide a solid base for going forward with engineering and economic studies in 2012/2013 to establish Karma as one of the premier gold projects in West Africa. There also remains significant potential to continue to increase the gold resource with further drilling in the future".

The Karma Project consists of five separate deposits, which are located in close proximity to each other. A summary of the resource estimates within a Whittle pit shell for each deposit is presented in the table below:

KARMA PROJECT IN PIT RESOURCE ESTIMATE^{(1)(2)(3)(4)(5)(6)(7)}
(Within Whittle pit shells)⁽⁶⁾

Deposit	Category	Cut Off Au g/t	Type	Tonnes	Grade (g/t)	Au--oz
GOULAGOU  I	Indicated	0.20	Oxide	6,651,000	0.62	132,500
		0.22	Transition	2,757,000	0.71	62,600
		0.50	Sulphide	5,739,000	1.07	197,100
			Subtotal	15,147,000	0.81	392,200
	Inferred	0.20	Oxide	1,518,000	0.79	38,400
		0.22	Transition	561,000	0.81	14,500
		0.50	Sulphide	2,762,000	1.04	92,400
			Subtotal	4,841,000	0.93	145,300
GOULAGOU  II	Indicated	0.20	Oxide	6,403,000	1.16	237,900
		0.22	Transition	1,835,000	1.44	85,000
		0.50	Sulphide	4,744,000	1.67	255,500
			Subtotal	12,982,000	1.39	578,400
	Inferred	0.20	Oxide	709,000	0.74	17,000
		0.22	Transition	339,000	1.05	11,400
		0.50	Sulphide	1,432,000	1.35	62,200
			Subtotal	2,480,000	1.14	90,600
KAO	Indicated	0.20	Oxide	9,552,000	0.87	268,300
		0.22	Transition	2,953,000	0.97	92,200
		0.50	Sulphide	11,743,000	1.22	459,900
			Subtotal	24,248,000	1.05	820,400
	Inferred	0.20	Oxide	2,355,000	0.60	45,100
		0.22	Transition	345,000	0.73	8,100
		0.50	Sulphide	4,654,000	1.22	182,700
			Subtotal	7,354,000	1.00	235,900
NAMI	Indicated	0.20	Oxide	656,000	0.96	20,200
		0.22	Transition	1,063,000	0.72	24,700
		0.22	Sulphide	1,561,000	0.82	40,900
			Subtotal	3,280,000	0.81	85,800
	Inferred	0.20	Oxide	127,000	0.85	3,500
		0.22	Transition	167,000	0.79	4,200
		0.22	Sulphide	198,000	0.74	4,700
			Subtotal	492,000	0.79	12,400
RAMBO	Indicated	0.20	Oxide	200,000	2.19	14,100
		0.22	Transition	261,000	2.83	23,800
		0.22	Sulphide	357,000	2.46	28,300
			Subtotal	818,000	2.51	66,200
	Inferred	0.20	Oxide	115,000	1.33	4,900
		0.22	Transition	51,000	0.53	900
		0.22	Sulphide	43,000	1.52	2,100
			Subtotal	209,000	1.17	7,900
TOTAL	Indicated	0.20	Oxide	23,462,000	0.89	672,900
		0.22	Transition	8,869,000	1.01	288,200
		0.22 & 0.50	Sulphide	24,145,000	1.26	981,700
			Total	56,476,000	1.07	1,942,800
TOTAL	Inferred	0.20	Oxide	4,825,000	0.70	108,900
		0.22	Transition	1,463,000	0.83	39,200
		0.22 & 0.50	Sulphide	9,090,000	1.18	344,100
			Total	15,378,000	1.00	492,200

1. Resource estimates were based on a gold price of US$1,415 per ounce, a 92% to 85%, 90% to 76% respective leach recoveries for oxide and transition and flotation recoveries of 89% to 96% for sulphides; oxide and transition mining costs of US$1.60/tonne and US$1.80 per tonne for sulphide; process costs of US$6.20/tonne for oxide and transition and US$17.00 per tonne for sulphide; and General & Administrative costs of US$1.70 tonne were used to determine the respective 0.20, 0.22 and 0.50 oxide, transition and sulphide open pit cut-off grades.
2. Au grades were estimated in a 5m x 5m x 5m block model (except Rambo at 2.5m x 2.5m x 2.5m blocks) from capped 2.0m composites utilizing inverse distance cubed interpolation. Composites were capped up to 45 g/t depending on the individual mineralized domain.
3. Mineral resources which are not mineral reserves do not have demonstrated economic viability. The estimate of mineral resources may be materially affected by environmental, permitting, legal, title, taxation, sociopolitical, marketing, or other relevant issues.
4. The quantity and grade of reported Inferred resources in this estimation are uncertain in nature and there has been insufficient exploration to define these Inferred resources as an Indicated or Measured mineral resource and it is uncertain if further exploration will result in upgrading them to an Indicated or Measured mineral resource category.
5. The mineral resources in this press release were estimated using the Canadian Institute of Mining, Metallurgy and Petroleum (CIM), CIM Standards on Mineral Resources and Reserves, Definitions and Guidelines prepared by the CIM Standing Committee on Reserve Definitions and adopted by CIM Council.
6. Material within Whittle pit shells have engineering mining aspects derived from the Sep 2012 Preliminary Economic Assessment applied to the global mineral inventory.
7. Readers are cautioned that at the time of this press release, the exploration permits covering the Goulagou I, Goulagou II, Rambo and Nami deposits are expired pending the issuance of an exploitation permit over the Goulagou I, Goulagou II and Rambo deposits by the Ministry of Mines for Burkina Faso. There is a reasonable expectation, however no guarantee, that in the near future that these exploitation permits will be issued. The exploration permit for the Kao deposit expires September 2013.

The resource estimation is based on a total of 1,220 diamond and reverse circulation drill holes for 183,374 metres. Subsequent to the January 2012 resource estimation, a total of 383 new diamond and reverse circulation holes for 77,641 metres are credited to the resource update.

Riverstone will continue with the on-going drill program to further extend and upgrade the resource quality of the 5 deposits and also to test regional targets throughout the remainder of 2012 and into 2013.

All reported resources fell within the limits of the mineralized wire frames. All interpolated grade blocks or partial blocks within the resource wire frames need to have at least three composites from two holes within 50 metres to be classified as Indicated Resource. Inferred Resources were determined from the remaining blocks, or partial blocks that lie within the wire frames.

KARMA PROJECT GLOBAL MINERAL INVENTORY ESTIMATE
(within and outside of Whittle pit shells)

Deposit	Category	Cut Off Au g/t	Type	Tonnes	Grade (g/t)	Au--oz
GOULAGOU  I	Indicated	0.20	Oxide	7,131,000	0.61	139,200
		0.22	Transition	3,338,000	0.67	71,900
		0.50	Sulphide	8,720,000	0.96	269,700
			Subtotal	19,189,000	0.78	480,800
	Inferred	0.20	Oxide	1,794,000	0.73	42,300
		0.22	Transition	1,039,000	0.67	22,400
		0.50	Sulphide	7,586,000	0.85	207,200
			Subtotal	10,419,000	0.81	271,900
GOULAGOU  II	Indicated	0.20	Oxide	6,480,000	1.15	239,000
		0.22	Transition	1,961,000	1.38	87,000
		0.50	Sulphide	5,920,000	1.56	296,600
			Subtotal	14,361,000	1.35	622,600
	Inferred	0.20	Oxide	805,000	0.70	18,200
		0.22	Transition	450,000	0.90	13,000
		0.50	Sulphide	4,884,000	1.12	176,400
			Subtotal	6,139,000	1.05	207,600
KAO	Indicated	0.20	Oxide	10,384,000	0.84	280,600
		0.22	Transition	3,303,000	0.93	98,500
		0.50	Sulphide	16,298,000	1.14	596,400
			Subtotal	29,985,000	1.01	975,500
	Inferred	0.20	Oxide	4,768,000	0.49	75,500
		0.22	Transition	1,562,000	0.51	25,700
		0.50	Sulphide	14,895,000	0.98	468,900
			Subtotal	21,225,000	0.84	570,100
NAMI	Indicated	0.20	Oxide	668,000	0.95	20,300
		0.22	Transition	1,091,000	0.71	25,000
		0.22	Sulphide	2,448,000	0.72	56,700
			Subtotal	4,207,000	0.75	102,000
	Inferred	0.20	Oxide	155,000	0.80	4,000
		0.22	Transition	191,000	0.75	4,600
		0.22	Sulphide	1,059,000	0.54	18,400
			Subtotal	1,405,000	0.60	27,000
RAMBO	Indicated	0.20	Oxide	206,000	2.14	14,200
		0.22	Transition	283,000	2.66	24,200
		0.22	Sulphide	518,000	1.95	32,400
			Subtotal	1,007,000	2.19	70,800
	Inferred	0.20	Oxide	187,000	1.03	6,200
		0.22	Transition	128,000	0.53	2,200
		0.22	Sulphide	901,000	1.05	30,500
			Subtotal	1,216,000	0.99	38,900
TOTAL	Indicated	0.20	Oxide	24,869,000	0.87	693,300
		0.22	Transition	9,976,000	0.96	306,700
		0.22 & 0.50	Sulphide	33,905,000	1.15	1,251,800
			Total	68,750,000	1.02	2,251,800
TOTAL	Inferred	0.20	Oxide	7,709,000	0.59	146,200
		0.22	Transition	3,369,000	0.63	67,800
		0.22 & 0.50	Sulphide	29,325,000	0.96	901,300
			Total	40,403,000	0.86	1,115,300

Assay data used as a basis in these resource estimates have been independently verified from original assay lab certificates.

The mineral resource estimates in this press release were prepared by Eugene Puritch, P.Eng., Antoine Yassa, P.Geo., and Yungang Wu, P.Geo of P&E, each an independent qualified person, as defined by National Instrument 43-101 ("NI 43-101").

Mr. Puritch has reviewed and approved the contents of this news release. Paul G. Anderson, MSc. P.Geo., the Company's Vice-President of Exploration, is Riverstone's Qualified Person for the purposes of NI 43-101 and has approved the technical content of this news release.

Riverstone is active in Burkina Faso, West Africa, where it holds a portfolio of four high quality exploration projects covering in excess of 2,000 square kilometres. The Company's flagship project is the Karma Project. The results of a Preliminary Economic Assessment have recently been released (see Company news release dated August 20, 2012 and NI 43-101 Technical Report titled, "Preliminary Economic Assessment Report for the Karma Project, Burkina Faso, West Africa", with an effective date of August 2, 2012, filed on SEDAR (www.sedar.com) September 17, 2012), highlighting the Karma Project to be a robust project.

Riverstone maintains a quality control program involving the use of repeat assays, inserted blanks and the use of certified standards from an accredited Canadian laboratory. All samples were prepared at the independent Abilab Burkina SARL laboratory in Ouagadougou, Burkina Faso, West Africa (part of the ALS Chemex Group), and assayed using standard fire assay with an atomic absorption finish, with samples grading over one gram per tonne gold re-assayed with a gravimetric finish, either in Burkina Faso or at an ALS Chemex facility in North Vancouver, British Columbia, Canada, or in Johannesburg, South Africa.

Addition information about the Company and its activities may be found on the Company's website at www.riverstoneresources.com and under the Company's profile at www.sedar.com.


ON BEHALF OF THE BOARD
"Dwayne L. Melrose"
Dwayne L. Melrose, President & CEO


For further information contact:

Vancouver Office:
Dwayne L. Melrose 604-801-5020
Email: info@riverstoneresources.com

Don Mosher, Corporate Development 604-685-6465
Raju Wani, Investor Relations 403-240-0555
Ron Cooper, Investor Relations 604-986-0112