LONDON -- This week has seen the FTSE 100 edge lower as evidence of weak economic growth in Europe and Asia continues to dominate the news. This has led most major commodity prices to weaken through the week, with precious metals falling particularly badly, while U.S. oil prices in particular benefited from fears over the effects of sanctions on Iran, leaving WTI crude to end the week up slightly.

Here are the latest prices, with this week's change in brackets:

Commodity

Price

Price Change

Price Change %

Brent Crude

$99.10/barrel

($0.90)

(0.9%)

WTI crude

$86.50/barrel

$1.70

2%

Natural gas

$2.88/MMBtu

$0.09

0.6%

Gold

$1,576.50/troy ounce

($37)

(2.3%)

Silver

$26.69/troy ounce

($1.42)

(5.1%)

Platinum

$1,404/troy ounce

($81)

(5.5%)

Palladium

$570/troy ounce

($31)

(5.2%)

Copper

$3.47/pound

$0.06

1.8%

Corn

$7.45/bushel

$0.46

6.6%

Wheat

188 pounds/ton

5 pounds

2.7%

In the U.S., extremely hot weather is hurting corn crops, meaning that harvest yields will be lower than expected this year. Last week saw a big leap in the price of corn, and this continued at a slower rate this week. However, although the price of corn rose, ETFS Corn ETC (LSE: CORN.L) ended the week down slightly, having tracked ahead of the underlying corn price in recent weeks.

Precious metals fell this week, with db Physical Platinum ETC (LSE: XPLA.L) and db Physical Silver ETC (LSE: XSIL.L) both falling slightly during the week thanks to a surplus of supply, flat industrial demand, and weaker investor sentiment in the U.S., where a further slice of quantitative easing now seems less likely. Reports of new U.S. sanctions against Iran helped oil and gas prices stayed broadly firm, although both ETFS Crude Oil ETC and ETFS Natural Gas ETC fell slightly over the course of the week.

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