By 12:15 local time the JSE all share index had declined 1.03%, with gold counters down 1.13%. Resources fell 1.84% and the platinum index dropped 0.72%.
After opening lower, the JSE extended its losses during the morning session, weighed by weaker global stock markets. Inflation concerns from Asia and the UK were dampening sentiment on global bourses, a trader noted.
By 12:15 local time the JSE all share index had declined 1.03%, with gold counters down 1.13%. Resources fell 1.84% and the platinum index dropped 0.72%. Banks were down 1.33%, financials shed 0.85% while industrials were down 0.36%.
The rand was bid at R7.00/$ from R6.97/$ at the JSE's previous close. Gold was quoted at $1,361.67 a troy ounce from $1,368/oz at the JSE's previous close, while platinum was at $1,667/oz from $1,678/oz before.
Asian markets were weaker, with the Nikkei closing off 0.31% and the Hang Seng shedding 1.4%.
Andrew Bryson, broker from BoE Stockbrokers said: "The JSE is taking a bit of strain at the moment, along with global markets, mainly due to concerns about inflation figures released in the East and the United Kingdom. The dollar has also firmed a little bit and this has led to profit taking."
Dow Jones Newswires reported that the FTSE 100 was down 1.12%, with sovereign debt concerns still weighing heavy on the markets. Mining stocks fell on fears of monetary policy tightening in China and as base metals traded lower. The FTSE 350 mining index lost 2.3%. Bank stocks dropped on concerns about the issue of Irish debt and data showed that the UK's annual inflation came in at 3.2% in October - above the Bank of England's 2% target but it had little impact on the market.
On the JSE, heavyweight Anglo American lost R8.40 or 2.47% to R331.00 and Sasol lost R3.64 or 1.08% to R333.51.
BHP Billiton , which on Monday abandoned its $39bn bid for Canadian fertiliser company Potash Corp. of Saskatchewan Inc, was down R6.50 or 2.42% to R262.50.
Among gold counters, Anglogold Ashanti lost R4.00 or 1.16% to R341.25 and Gold Fields shed R1.30 or 1.07% to R120.36. This morning The National Union of Mineworkers NUM threatened to ground Goldfields entire operation as the strike at the mine's Deep South unit entered its third day. Over 3,000 mineworkers at Gold Fields's South Deep operation were taking part in the strike and there was a "great possibility of a sweeping strike action" across all Gold Fields operations, the union warned.
Among platinums, Anglo Platinum was down R5.48 to R703.32 and Impala Platinum lost R1.25 to R214.00.
Mining group Lonmin plc was trading R4.35 or 2.11% lower at R201.65.
Financial services group Mercantile Bank Holdings said Tuesday that both its earnings and headline earnings per share for the year ended December 2010 are expected to decrease by 30% to 40% compared with the corresponding period last year.
This decline is mainly attributable to the negative endowment effect resulting from the lower interest rate environment in South Africa and the high level of unleveraged capital of the company.
Mercantile's shares were trading 25 cents lower at R36.30.