The most common and most likely answer to this crossword clue is the 5 letter word CARAT
I've seen this crossword clue in The Times
C
A
R
A
T
More clues leading to the result CARAT
- Wagon broken by a weight of stones
- Weight of ice beginning to accumulate in farm vehicle
- Unit employed with rocks to lug round area
- Vehicle made to carry a weight
- Vehicle bearing a quantity of weight
- Carry round a little weight
- In trolley, a gold weight
- Measure area covered by bear
- Unit of weight around a ton, about right?
- Vehicle’s parked over half that — it’s worth its weight in gold
Buddy explains!

The straight part
We know that "weight of stones" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case weight of stones = carat.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does CARAT mean?
CARAT noun- A unit of weight for precious stones and pearls, equivalent to 200 milligrams.
- Any of several units of weight, varying from 189 to 212 mg, the weight of a carob seed.
- A measure of the purity of gold, pure gold being 24 carats.