Ruling on stoning the Jamaraat with a piece ofconcrete

What is the ruling on stoning the Jamaraat witha piece of concrete? It
looked the same as the stones to me, until someone pointed that outto
me on the second day. Do I have to repeat the stoning? What is the
ruling on stoning the Jamaraat with a piece of abig rock after
breaking it into small pieces?
Praise be to Allah.
The majority of fuqaha' stipulated that the Jamaraat should be stoned
with pebbles, which are small stones of whatever type of rock.
Concrete is not rock, so it is not acceptable, according to the
majority.
Ibn Qudaamah (may Allahhave mercy on him) said: It is acceptable to
stone the Jamaraat with anything that is called pebbles, which are
small stones, whether they are black or white or red, and whether they
are marble, flint, granite and so on. This is the view of Maalik and
ash-Shaafa'i. al-Qaadi said: Marble, buraam and kadhdhaan (types of
rock)are not acceptable. And we may understand from his words that
marble andsolid stones are not acceptable either. Abu Haneefah said:
It is permissible to use dried clay or mud, or anything that comes
from the earth. Something similar was stated by ath-Thawri.It was
narrated from Sakeenah bint al-Husayn that she stoned the Jamarah, and
a man was handing pebbles to her, and she was saying takbeer with each
throw. And she dropped a pebble, so she threw her ring.
We also have a report that the Prophet (blessings and peace of Allah
be upon him) stonedthe Jamaraat with pebbles, and he told the people
to throw pebbles the size of chickpeas, so nothing other than pebbles
is to be picked up,and that includes pebbles of all types. It is not
permissible to single out any particular type without evidence, or to
add anything else to it, because it is a topic in which there is no
room for analogy.
End quote from al-Mughni, 3/218
In al-Mawsoo'ah al-Fiqhiyyah (15/277) it says: When stoning the
jamaraat, it is stipulated that the pebbles be of stone, according to
the majority of fuqaha' (Maalikis, Shaafa'is and Hanbalis). So it is
not permissible to use gold, silver, iron, lead, wood, clay, seeds,
dust, pearls, antimony or plaster in their view, because the Prophet
(blessings and peace of Allah be upon him) threw pebbles and
instructed us to throw pebbles the size of chickpeas, so nothing else
should be picked up. The Shaafaa'is allowed stoning the Jamaraat
withall kinds of stones.
The Hanafis were of the view that it is permissible to stone the
Jamaraat with all kinds of things that come from the earth, such as
stones, mud and clay, and everything with which it is permissible to
do tayammum, but it is not permissible to use wood, amber, pearls or
gemstones, because they are not from the earth. End quote.
Based on this, there is nothing wrong with breaking stones or large
rocks and stoning the Jamaraat with them.
As for throwing concrete or pieces of brick, it is not acceptable
according to the majority, although it is acceptable according to the
Hanafis. However the view of the majority is more on the safe side.
Shaykh Ibn 'Uthaymeen (may Allah have mercy onhim) was asked: What is
the ruling on stoning the Jamaraat with pieces of concrete?
He replied: Some scholars think that the stones that are taken from
concrete are not acceptable for stoning the Jamaraat, unless this
piece of concrete contains stone. Ifit contains stone then there is
nothing wrong with it.
End quote from Majmoo' Fataawa Ibn 'Uthaymeen, 23/125
To sum up: If on the first day you threw pieces of concrete in which
there was no stone, then your stoning was not valid according to the
majority, and you have to sacrifice a sheep, the meat of which is to
be distributed among the poor of the Haram; you may delegate someone
to do that on your behalf.
If you cannot afford the price of a sheep, then you do not have to do anything.
And Allah knows best.