LONDON -- The FTSE 100 (INDEX: ^FTSE) toyed with us this week, teasing us with a rise to 5,873 points early on Tuesday, only to dash our hopes and fall back to 5,852 points by the end of Friday, just 5 points up on the week.

And if you think that's all meaningless, you're right. Fools just aren't interested in the short-term meanderings of an ultimately meaningless number. But we are interested in how companies in the various FTSE indices fare.

Standard Life (LSE: SL.L)
Financials had a good week, with insurer and investment manager Standard Life gaining 19 pence (7.4%) to 276.5 pence on the back of interim results that saw its halftime dividend payout boosted by 6.5% to 4.9 pence per share -- and that's in line with the current forecasted annual yield of around 5.5%.

Of particular importance was the news that the company's exposure to government debt in Greece, Spain, Portugal, Ireland, and Italy amounts to less than 50 million pounds.

Eurasian Natural Resources (LSE: ENRC.L)
Miners have been squeezed of late, but Eurasian Natural Resources was crushed this week, falling 56 pence (13%) to 369.7 pence in the week it released its halftime results.

The Kazakhstan-based natural-resources group saw profits fall 60% in the six months, down to $463 million from $1.2 billion in the first half of 2011, blamed on market conditions stemming from the slowdown in Chinese demand.

Rank Group (LSE: RNK.L)
Rank Group gained a nice 12.7 pence (11%) to 132.7 pence after the gaming and leisure operator released full year results. Revenue for the year to June 30 rose by 3.4% to 600 million pounds, with adjusted pre-tax profit up 9% to 61.5 million, and adjusted earnings per share were boosted 13.7% to 11.6 pence.

That allowed the company to raise its dividend by 35% to 3.6 pence per share -- it's a modest yield of 2.7%, but it's more than three times covered by earnings and is certainly headed in the right direction.

Lonmin (LSE: LMI.L)
South Africa-based miner Lonmin crashed by 113 pence (15%) to 634 pence for reasons unrelated to falling metals and minerals prices. Far worse, the fall came after more than 30 protesting workers at the company's Marikana platinum mine were killed by police using automatic weapons.

With the protests at the mine becoming increasingly politicized, it's hard to guess how things will end -- but it does put our everyday ups and downs into some sort of real-world perspective.

What now?
As usual, this week's FTSE trading provided some large share-price movements -- and perhaps some buying opportunities. Indeed, legendary investor Warren Buffett has spent more than $1 billion buying the shares of one of the U.K.'s most successful FTSE large caps.

Clearly, he thinks there are bargains to be had within Britain's stock market, and you can discover the details of his investment -- including the price he paid -- by reading this special report. The report -- "The One U.K. Share Warren Buffett Loves" -- is free and can be accessed immediately.

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