* FTSE 100 down 0.3 pct
* Rio Tinto drags after earnings disappoint
* Lack of dividend sends StanChart down 6 pct
* William Hill jumps on stronger online revenue (ADVISORY- Follow European and UK stock markets in real time on the Reuters Live Markets blog on Eikon - see cpurl://apps.cp./cms/?pageId=livemarkets)
LONDON, Aug 2 (Reuters) - Britain's major share index slipped on Wednesday as basic resources and financial stocks weighed on another full day of earnings with Standard Chartered and Rio Tinto among the large companies reporting disappointing results.
The FTSE 100 dipped 0.3 percent after two robust sessions of gains, dragged down by heavyweight miners Rio Tinto and Glencore, with financials the biggest sector weight.
Standard Chartered shares fell 6.3 percent, their worst day in nine months, despite the bank reporting a 93 percent increase in first-half profit, as investors' hopes of a resumed dividend payout were dashed.
"Management have always said it's a long haul, but people dare to dream it's going to be a bit quicker than that," said Eric Moore, manager of the UK Income fund at Miton.
"After encouraging HSBC numbers people maybe felt that StanChart would be quite good, but the top line growth isn't there," he added.
Rio Tinto fell 2.8 percent after the miner's earnings missed forecasts, though they more than doubled thanks to higher commodity prices.
"While slightly behind our expectations, we still consider the numbers to be decent," said Shore Capital analysts.
"We were disappointed at the increased buyback - we would have preferred to see a higher dividend instead," they added, referring to Rio's increased share buy-back of $1 billion by end of 2017.
Peer Glencore also fell 1.2 percent.
Rolls Royce fell 3.7 percent, giving back some of the previous session's strong results-driven gains, despite Bernstein and Goldman Sachs raising price targets on the engine maker.
Old Mutual led gains, up 2.8 percent after its subsidiary Nedbank reported results.
Analysts at KBW said the bank's non-interest revenue grew by 3.3 percent and its common equity Tier 1 ratio - a measure of the bank's viability - rose.
BAE Systems flipped from a boost to a drag on the index, closing down 2.7 percent although its first-half earnings beat forecasts. The firm flagged a softening in demand in cyber and intelligence.
Mid-caps held up slightly better than the large companies, dipping 0.1 percent.
Betting shop William Hill led gains, jumping 6.1 percent after its first-half results showed revenue from online channels were up 5 percent.
"William Hill is cheap, trading on a full-year 2017 price-to-earnings of 10.5 times, free cash flow yield of 7.6 percent, dividend yield of 5 percent. Regulation risk is high but momentum is strong in key online division," said Barclays analysts.
Auto Trader fell 4.8 percent, among the worst-performing on the STOXX 600, after JP Morgan cut its ratings on it and German peer Scout24.
"Online classifieds have been darling stocks over the past five years, but we see clouds on the horizon," said JP Morgan analysts.
"We downgrade Auto Trader to underweight from neutral on valuation grounds and weakening macro data," they added, pointing to weak new car sales as an indicator the classified car website could underperform. (Reporting by Helen Reid; Editing by Andrew Heavens)