LONDON -- The FTSE 100 (INDEX: ^FTSE) went into decline this week, falling 74 points (1.3%) from last week's close of 5,853 points, to end this week on around 5,740. It was all due to news of deteriorating economic conditions in Spain, coupled with increasing unrest over austerity measures both there and in Greece -- it's looking more and more likely that Spain will be seeking a euro bailout.

But independently of whatever Europe was doing, individual U.K. stocks were moving.

QinetiQ (LSE: QQ.L)
Defense and aerospace engineer QinetiQ released a trading update on Monday, and it helped the stock to a gain on the week of 17.5 pence (9.3%) to 189.5 pence. That brought the price gain to 60% over the past 12 months, helping reinforce the engineering recovery that is under way.

First-half performance has been "stronger than originally expected," and the company now expects to at least match current forecasts for the full year. But it's not all shining light, as although U.K. business continues to perform well, QinetiQ's U.S. subsidiaries are still facing contract award delays.

Tate & Lyle (LSE: TATE.L)
FTSE 100 constituent Tate & Lyle had a good week, ending 17.5 pence (2.5%) up at 666.5 pence. The driver was an upbeat interim update, that told us that everything is going according to plan.

After having sold its sugar refining business last year, the slimmed-down Tate's Bulk Ingredients division enjoyed good sales of liquid sweeteners, while its Specialty Foods division is in line for volume growth. There's a 4% dividend forecast for the full year, and that's looking safe.

Shanks (LSE: SKS.L)
Waste management specialist Shanks Group issued a profit warning this week, which pushed the shares down 6.2 pence (7.5%) to end the week at 82.4 pence. The statement, ahead of interim results due on Nov. 8, told us that profits will be "slightly below" current market expectations, after trading conditions in its U.K. and Dutch solid waste divisions have deteriorated since July.

Shanks is a company that has had downturns before but has bounced back, so could there be another recovery due?

Topps Tiles (LSE: TPT.L)
Topps Tiles lost 4 pence (8.5%) to 46.5 pence in the week it revealed a trading update that really looked pretty good. The fourth quarter was apparently strong, and full-year performance should be in line with current forecasts, so we should expect pre-tax profit of between 12.7 million and 14 million pounds.

The fall was most likely just due to a bit of profit taking after the stock had been up as high as 52 pence recently, taking it up over 50% during the past 12 months.

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.

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